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  • would there be such case of jumping, if yes how?

    - by Pooria
    I have an issue in the mind and that is since the jump instruction changes EIP register by adding signed offsets to it(if I'm not making a mistake here), on IA-32 architecture how would going upward in memory from location 0x7FFFFFFF(biggest positive number in signed logic) to 0x80000000(least negative number in signed logic) be possible? or maybe there shouldn't be such jump due to the nature of signed logic?

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  • PHP array question.

    - by TaG
    How do I show the dates number format next to its name in the array using PHP? So that the number format is saved in the database and the month name is displayed? Here is the php code. $month_options = array("Month", "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December");

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  • How to find missing alpha values in sets of data within same table in SQL

    - by Jeff
    I have a table of many values where one column has the WO Number, and another column has the Resource ID. I need to be able to find all the WO numbers that do not have a resource value of "RW". Here is an example of the typical information. I need to be able to know that work order 5678 does not have an "RW" Resource ID. WO Number - Resource ID 1234 - IN 1234 - WE 1234 - AS 1234 - RW 5678 - PR 5678 - WE 5678 - IN 5678 - AS

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  • Without width printing format in C

    - by yCalleecharan
    Hi, in C if I have a printf statement containing say "%.2f", it says that the precision is 2 digits after the decimal place. I haven't explicitly specify the width. I have two questions: Is this good programming practice?; Is without specifying the width means that the width of the field will get adjusted automatically when printing the number, irrespective of the number of digits it contains? Thanks a lot...

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  • Select only half the records

    - by coffeeaddict
    I am trying to figure out how to select half the records where an ID is null. I want half because I am going to use that result set to update another ID field. Then I am going to update the rest with another value for that ID field. So essentially I want to update half the records someFieldID with one number and the rest with another number splitting the update basically between two values for someFieldID the field I want to update.

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  • Python: Random integer

    - by user3696440
    I been hitting a wall thats been keeping me from tinkering on a game. class Damage: def shortsword(): shortsword=randint(1,6)+1 shortsword=int(shortsword) return shortsword I been wanting this number to pop up as part of a message on print and then use the same number as part of another function to help with subtracting of health on the target. Though each time I grab this it is always going to change.

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  • JQuery height and units

    - by Parhs
    Hello.. I know that height() method of jquery returns a number unitless... How can i be sure that this number is in the unit i want? I want to work with centimeter cm any ideas?

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  • find nth digit in C

    - by kokkch
    i spend more than a day to solve this and i can't. I have a function name int get_nth_digit (int x, int pos); which takes as entering the number given by the user(x) and a number that represents the position in which the user wishes to return the item. How can do this with C program? can you help me pls???? thx

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  • Android Password GUI

    - by ranjanarr
    I am looking for Android GUI which is wheel type number lock, with numbers on the wheel. The password GUI looks like a wheel with numbers on it and user can roll the wheel to select a number when wheel stops, only the numbers are visible that are on the surface of wheel.

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  • Playing multiple FLVs at the same time feasible?

    - by eb_Dev
    Hi, Is it feasible to play a number of FLV files at the same time on one SWF? Basically I have a brief to create a video banner with a number of FLVs of people playing at the same time but starting at different points in the videos. My concerns are with loading times, memory consumption and the starting of each FLV at a different point and looping it. The FLVs will be stored on a server and pseudo-streamed. Any tips would be greatly appreciated. Thanks, eb_dev

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  • Loop through array, print with string.

    - by Adam
    I have a simple array like: var myArr=["one","two","three"]; an I have a counting loop, which increases the value of var i by one. What I want to do is print the next value from the array each time the loop runs, next to a text string, like so: alert('value number '+myArr[i]+); But for some reason I can't get this to work. The following code works, so I'm assuming I'm not calling the counter right: alert('value number '+myArr[0]+);

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  • SQL & PHP - Which is faster mysql_num_rows() or 'select count()'?

    - by Joel
    I'm just wondering which method is the most effective if I'm literally just wanting to get the number of rows in a table. $res = mysql_query("SELECT count(*) as `number` FROM `table1`"); $count = mysql_fetch_result($res,0,'number'); or $res = mysql_query("SELECT `ID` FROM `table1`"); $count = mysql_num_rows($res); Anyone done any decent testing on this?

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  • Need help with a regex (sed)

    - by nimo9367
    I want to transform a line that looks like this: any text #any text# ===#text#text#text#===# into: any text #any text# ===#texttexttext===# As you can see above I want to remove the # between ===# and ===# The number of # that are supposed to be removed can be any number. Can I do this with sed?

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  • Jdbc - Connect remote Mysql Database error

    - by Guilherme Ruiz
    I'm using JDBC to connect my program to a MySQL database. I already put the port number and yes, my database have permission to access. When i use localhost work perfectly, but when i try connect to a remote MySQL database, show this error on console. java.lang.ExceptionInInitializerError Caused by: java.lang.NumberFormatException: null at java.lang.Integer.parseInt(Integer.java:454) at java.lang.Integer.parseInt(Integer.java:527) at serial.BDArduino.<clinit>(BDArduino.java:25) Exception in thread "main" Java Result: 1 CONSTRUÍDO COM SUCESSO (tempo total: 1 segundo) Thank you in Advance ! MAIN CODE /* * To change this template, choose Tools | Templates * and open the template in the editor. */ package serial; import gnu.io.CommPort; import gnu.io.CommPortIdentifier; import gnu.io.SerialPort; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import javax.swing.JFrame; import javax.swing.JOptionPane; /** * * @author Ruiz */ public class BDArduino extends JFrame { static boolean connected = false; static int aux_sql8 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin8")); static int aux_sql2 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin2")); CommPort commPort = null; SerialPort serialPort = null; InputStream inputStream = null; static OutputStream outputStream = null; String comPortNum = "COM10"; int baudRate = 9600; int[] intArray = {2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13}; /** * Creates new form ArduinoTest */ public BDArduino() { //super("Arduino Test App"); initComponents(); } class Escrita extends Thread { private int i; public void run() { while (true) { System.out.println("Número :" + i++); } } } //public void actionPerformed(ActionEvent e) { // String arg = e.getActionCommand(); public static void writeData(int a) throws IOException { outputStream.write(a); } public void action(String arg) { System.out.println(arg); Object[] msg = {"Baud Rate: ", "9600", "COM Port #: ", "COM10"}; if (arg == "connect") { if (connected == false) { new BDArduino.ConnectionMaker().start(); } else { closeConnection(); } } if (arg == "disconnect") { serialPort.close(); closeConnection(); } if (arg == "p2") { System.out.print("Pin #2\n"); try { outputStream.write(intArray[0]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p3") { System.out.print("Pin #3\n"); try { outputStream.write(intArray[1]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p4") { System.out.print("Pin #4\n"); try { outputStream.write(intArray[2]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p5") { System.out.print("Pin #5\n"); try { outputStream.write(intArray[3]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p6") { System.out.print("Pin #6\n"); try { outputStream.write(intArray[4]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p7") { System.out.print("Pin #7\n"); try { outputStream.write(intArray[5]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p8") { System.out.print("Pin #8\n"); try { outputStream.write(intArray[6]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p9") { System.out.print("Pin #9\n"); try { outputStream.write(intArray[7]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p10") { System.out.print("Pin #10\n"); try { outputStream.write(intArray[8]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p11") { System.out.print("Pin #11\n"); try { outputStream.write(intArray[9]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p12") { System.out.print("Pin #12\n"); try { outputStream.write(intArray[10]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } if (arg == "p13") { System.out.print("Pin #12\n"); try { outputStream.write(intArray[11]); }//end try catch (IOException e12) { e12.printStackTrace(); System.exit(-1); }//end catch } } //******************************************************* //Arduino Connection *************************************** //****************************************************** void closeConnection() { try { outputStream.close(); } catch (Exception ex) { ex.printStackTrace(); String cantCloseConnectionMessage = "Can't Close Connection!"; JOptionPane.showMessageDialog(null, cantCloseConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } connected = false; System.out.print("\nDesconectado\n"); String disconnectedConnectionMessage = "Desconectado!"; JOptionPane.showMessageDialog(null, disconnectedConnectionMessage, "Desconectado", JOptionPane.INFORMATION_MESSAGE); }//end closeConnection() void connect() throws Exception { String portName = comPortNum; CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName); if (portIdentifier.isCurrentlyOwned()) { System.out.println("Error: Port is currently in use"); String portInUseConnectionMessage = "Port is currently in use!\nTry Again Later..."; JOptionPane.showMessageDialog(null, portInUseConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } else { commPort = portIdentifier.open(this.getClass().getName(), 2000); if (commPort instanceof SerialPort) { serialPort = (SerialPort) commPort; serialPort.setSerialPortParams(baudRate, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); outputStream = serialPort.getOutputStream(); } else { System.out.println("Error: Only serial ports are handled "); String onlySerialConnectionMessage = "Serial Ports ONLY!"; JOptionPane.showMessageDialog(null, onlySerialConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } }//end else //wait some time try { Thread.sleep(300); } catch (InterruptedException ie) { } }//end connect //******************************************************* //*innerclasses****************************************** //******************************************************* public class ConnectionMaker extends Thread { public void run() { //try to make a connection try { connect(); } catch (Exception ex) { ex.printStackTrace(); System.out.print("ERROR: Cannot connect!"); String cantConnectConnectionMessage = "Cannot Connect!\nCheck the connection settings\nand/or your configuration\nand try again!"; JOptionPane.showMessageDialog(null, cantConnectConnectionMessage, "ERROR", JOptionPane.ERROR_MESSAGE); } //show status serialPort.notifyOnDataAvailable(true); connected = true; //send ack System.out.print("\nConnected\n"); String connectedConnectionMessage = "Conectado!"; JOptionPane.showMessageDialog(null, connectedConnectionMessage, "Conectado", JOptionPane.INFORMATION_MESSAGE); }//end run }//end ConnectionMaker /** * This method is called from within the constructor to initialize the form. * WARNING: Do NOT modify this code. The content of this method is always * regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // <editor-fold defaultstate="collapsed" desc="Generated Code"> private void initComponents() { btnp2 = new javax.swing.JButton(); btncon = new javax.swing.JButton(); btndesc = new javax.swing.JButton(); btnp3 = new javax.swing.JButton(); btnp4 = new javax.swing.JButton(); btnp5 = new javax.swing.JButton(); btnp9 = new javax.swing.JButton(); btnp6 = new javax.swing.JButton(); btnp7 = new javax.swing.JButton(); btnp8 = new javax.swing.JButton(); btn13 = new javax.swing.JButton(); btnp10 = new javax.swing.JButton(); btnp11 = new javax.swing.JButton(); btnp12 = new javax.swing.JButton(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); btnp2.setText("2"); btnp2.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp2MouseClicked(evt); } }); btncon.setText("Conectar"); btncon.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnconMouseClicked(evt); } }); btndesc.setText("Desconectar"); btndesc.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btndescMouseClicked(evt); } }); btnp3.setText("3"); btnp3.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp3MouseClicked(evt); } }); btnp4.setText("4"); btnp4.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp4MouseClicked(evt); } }); btnp5.setText("5"); btnp5.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp5MouseClicked(evt); } }); btnp9.setText("9"); btnp9.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp9MouseClicked(evt); } }); btnp6.setText("6"); btnp6.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp6MouseClicked(evt); } }); btnp7.setText("7"); btnp7.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp7MouseClicked(evt); } }); btnp8.setText("8"); btnp8.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp8MouseClicked(evt); } }); btn13.setText("13"); btn13.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btn13MouseClicked(evt); } }); btnp10.setText("10"); btnp10.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp10MouseClicked(evt); } }); btnp11.setText("11"); btnp11.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp11MouseClicked(evt); } }); btnp12.setText("12"); btnp12.addMouseListener(new java.awt.event.MouseAdapter() { public void mouseClicked(java.awt.event.MouseEvent evt) { btnp12MouseClicked(evt); } }); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addGap(20, 20, 20) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false) .addGroup(layout.createSequentialGroup() .addComponent(btncon) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) .addComponent(btndesc)) .addGroup(layout.createSequentialGroup() .addComponent(btnp6, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp7, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp8, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp9, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(btnp10, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp11, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp12, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btn13, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)) .addGroup(layout.createSequentialGroup() .addComponent(btnp2, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp3, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp4, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(btnp5, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE))) .addContainerGap(20, Short.MAX_VALUE)) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addContainerGap() .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(btncon) .addComponent(btndesc)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 20, Short.MAX_VALUE) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp2) .addComponent(btnp3) .addComponent(btnp4) .addComponent(btnp5)) .addGap(18, 18, 18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp6) .addComponent(btnp7) .addComponent(btnp8) .addComponent(btnp9)) .addGap(18, 18, 18) .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(btnp10) .addComponent(btnp11) .addComponent(btnp12) .addComponent(btn13)) .addGap(22, 22, 22)) ); pack(); }// </editor-fold> private void btnp2MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p2"); } private void btnconMouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("connect"); } private void btndescMouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("disconnect"); } private void btnp3MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p3"); } private void btnp4MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p4"); } private void btnp5MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here action("p5"); } private void btnp9MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p9"); } private void btnp6MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p6"); } private void btnp7MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p7"); } private void btnp8MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p8"); } private void btn13MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p13"); } private void btnp10MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p10"); } private void btnp11MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p11"); } private void btnp12MouseClicked(java.awt.event.MouseEvent evt) { // TODO add your handling code here: action("p12"); } /** * @param args the command line arguments */ public static void main(String args[]) throws IOException { /* Set the Nimbus look and feel */ //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) "> /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html */ try { for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) { if ("Nimbus".equals(info.getName())) { javax.swing.UIManager.setLookAndFeel(info.getClassName()); break; } } } catch (Exception e) { } //</editor-fold> /* Create and display the form */ java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new BDArduino().setVisible(true); } }); //} while (true) { // int sql8 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin8")); if (connected == true && sql8 != aux_sql8) { aux_sql8 = sql8; if(sql8 == 1){ writeData(2); }else{ writeData(3); } } int sql2 = Integer.parseInt(Sql.getDBinfo("SELECT * FROM arduinoData WHERE id=1", "pin2")); if (connected == true && sql2 != aux_sql2) { aux_sql2 = sql2; if(sql2 == 1){ writeData(4); }else{ writeData(5); } } try { Thread.sleep(500); } catch (InterruptedException e) { e.printStackTrace(); } } } // Variables declaration - do not modify private javax.swing.JButton btn13; private javax.swing.JButton btncon; private javax.swing.JButton btndesc; private javax.swing.JButton btnp10; private javax.swing.JButton btnp11; private javax.swing.JButton btnp12; private javax.swing.JButton btnp2; private javax.swing.JButton btnp3; private javax.swing.JButton btnp4; private javax.swing.JButton btnp5; private javax.swing.JButton btnp6; private javax.swing.JButton btnp7; private javax.swing.JButton btnp8; private javax.swing.JButton btnp9; // End of variables declaration }

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  • Using an alternate JSON Serializer in ASP.NET Web API

    - by Rick Strahl
    The new ASP.NET Web API that Microsoft released alongside MVC 4.0 Beta last week is a great framework for building REST and AJAX APIs. I've been working with it for quite a while now and I really like the way it works and the complete set of features it provides 'in the box'. It's about time that Microsoft gets a decent API for building generic HTTP endpoints into the framework. DataContractJsonSerializer sucks As nice as Web API's overall design is one thing still sucks: The built-in JSON Serialization uses the DataContractJsonSerializer which is just too limiting for many scenarios. The biggest issues I have with it are: No support for untyped values (object, dynamic, Anonymous Types) MS AJAX style Date Formatting Ugly serialization formats for types like Dictionaries To me the most serious issue is dealing with serialization of untyped objects. I have number of applications with AJAX front ends that dynamically reformat data from business objects to fit a specific message format that certain UI components require. The most common scenario I have there are IEnumerable query results from a database with fields from the result set rearranged to fit the sometimes unconventional formats required for the UI components (like jqGrid for example). Creating custom types to fit these messages seems like overkill and projections using Linq makes this much easier to code up. Alas DataContractJsonSerializer doesn't support it. Neither does DataContractSerializer for XML output for that matter. What this means is that you can't do stuff like this in Web API out of the box:public object GetAnonymousType() { return new { name = "Rick", company = "West Wind", entered= DateTime.Now }; } Basically anything that doesn't have an explicit type DataContractJsonSerializer will not let you return. FWIW, the same is true for XmlSerializer which also doesn't work with non-typed values for serialization. The example above is obviously contrived with a hardcoded object graph, but it's not uncommon to get dynamic values returned from queries that have anonymous types for their result projections. Apparently there's a good possibility that Microsoft will ship Json.NET as part of Web API RTM release.  Scott Hanselman confirmed this as a footnote in his JSON Dates post a few days ago. I've heard several other people from Microsoft confirm that Json.NET will be included and be the default JSON serializer, but no details yet in what capacity it will show up. Let's hope it ends up as the default in the box. Meanwhile this post will show you how you can use it today with the beta and get JSON that matches what you should see in the RTM version. What about JsonValue? To be fair Web API DOES include a new JsonValue/JsonObject/JsonArray type that allow you to address some of these scenarios. JsonValue is a new type in the System.Json assembly that can be used to build up an object graph based on a dictionary. It's actually a really cool implementation of a dynamic type that allows you to create an object graph and spit it out to JSON without having to create .NET type first. JsonValue can also receive a JSON string and parse it without having to actually load it into a .NET type (which is something that's been missing in the core framework). This is really useful if you get a JSON result from an arbitrary service and you don't want to explicitly create a mapping type for the data returned. For serialization you can create an object structure on the fly and pass it back as part of an Web API action method like this:public JsonValue GetJsonValue() { dynamic json = new JsonObject(); json.name = "Rick"; json.company = "West Wind"; json.entered = DateTime.Now; dynamic address = new JsonObject(); address.street = "32 Kaiea"; address.zip = "96779"; json.address = address; dynamic phones = new JsonArray(); json.phoneNumbers = phones; dynamic phone = new JsonObject(); phone.type = "Home"; phone.number = "808 123-1233"; phones.Add(phone); phone = new JsonObject(); phone.type = "Home"; phone.number = "808 123-1233"; phones.Add(phone); //var jsonString = json.ToString(); return json; } which produces the following output (formatted here for easier reading):{ name: "rick", company: "West Wind", entered: "2012-03-08T15:33:19.673-10:00", address: { street: "32 Kaiea", zip: "96779" }, phoneNumbers: [ { type: "Home", number: "808 123-1233" }, { type: "Mobile", number: "808 123-1234" }] } If you need to build a simple JSON type on the fly these types work great. But if you have an existing type - or worse a query result/list that's already formatted JsonValue et al. become a pain to work with. As far as I can see there's no way to just throw an object instance at JsonValue and have it convert into JsonValue dictionary. It's a manual process. Using alternate Serializers in Web API So, currently the default serializer in WebAPI is DataContractJsonSeriaizer and I don't like it. You may not either, but luckily you can swap the serializer fairly easily. If you'd rather use the JavaScriptSerializer built into System.Web.Extensions or Json.NET today, it's not too difficult to create a custom MediaTypeFormatter that uses these serializers and can replace or partially replace the native serializer. Here's a MediaTypeFormatter implementation using the ASP.NET JavaScriptSerializer:using System; using System.Net.Http.Formatting; using System.Threading.Tasks; using System.Web.Script.Serialization; using System.Json; using System.IO; namespace Westwind.Web.WebApi { public class JavaScriptSerializerFormatter : MediaTypeFormatter { public JavaScriptSerializerFormatter() { SupportedMediaTypes.Add(new System.Net.Http.Headers.MediaTypeHeaderValue("application/json")); } protected override bool CanWriteType(Type type) { // don't serialize JsonValue structure use default for that if (type == typeof(JsonValue) || type == typeof(JsonObject) || type== typeof(JsonArray) ) return false; return true; } protected override bool CanReadType(Type type) { if (type == typeof(IKeyValueModel)) return false; return true; } protected override System.Threading.Tasks.Taskobject OnReadFromStreamAsync(Type type, System.IO.Stream stream, System.Net.Http.Headers.HttpContentHeaders contentHeaders, FormatterContext formatterContext) { var task = Taskobject.Factory.StartNew(() = { var ser = new JavaScriptSerializer(); string json; using (var sr = new StreamReader(stream)) { json = sr.ReadToEnd(); sr.Close(); } object val = ser.Deserialize(json,type); return val; }); return task; } protected override System.Threading.Tasks.Task OnWriteToStreamAsync(Type type, object value, System.IO.Stream stream, System.Net.Http.Headers.HttpContentHeaders contentHeaders, FormatterContext formatterContext, System.Net.TransportContext transportContext) { var task = Task.Factory.StartNew( () = { var ser = new JavaScriptSerializer(); var json = ser.Serialize(value); byte[] buf = System.Text.Encoding.Default.GetBytes(json); stream.Write(buf,0,buf.Length); stream.Flush(); }); return task; } } } Formatter implementation is pretty simple: You override 4 methods to tell which types you can handle and then handle the input or output streams to create/parse the JSON data. Note that when creating output you want to take care to still allow JsonValue/JsonObject/JsonArray types to be handled by the default serializer so those objects serialize properly - if you let either JavaScriptSerializer or JSON.NET handle them they'd try to render the dictionaries which is very undesirable. If you'd rather use Json.NET here's the JSON.NET version of the formatter:// this code requires a reference to JSON.NET in your project #if true using System; using System.Net.Http.Formatting; using System.Threading.Tasks; using System.Web.Script.Serialization; using System.Json; using Newtonsoft.Json; using System.IO; using Newtonsoft.Json.Converters; namespace Westwind.Web.WebApi { public class JsonNetFormatter : MediaTypeFormatter { public JsonNetFormatter() { SupportedMediaTypes.Add(new System.Net.Http.Headers.MediaTypeHeaderValue("application/json")); } protected override bool CanWriteType(Type type) { // don't serialize JsonValue structure use default for that if (type == typeof(JsonValue) || type == typeof(JsonObject) || type == typeof(JsonArray)) return false; return true; } protected override bool CanReadType(Type type) { if (type == typeof(IKeyValueModel)) return false; return true; } protected override System.Threading.Tasks.Taskobject OnReadFromStreamAsync(Type type, System.IO.Stream stream, System.Net.Http.Headers.HttpContentHeaders contentHeaders, FormatterContext formatterContext) { var task = Taskobject.Factory.StartNew(() = { var settings = new JsonSerializerSettings() { NullValueHandling = NullValueHandling.Ignore, }; var sr = new StreamReader(stream); var jreader = new JsonTextReader(sr); var ser = new JsonSerializer(); ser.Converters.Add(new IsoDateTimeConverter()); object val = ser.Deserialize(jreader, type); return val; }); return task; } protected override System.Threading.Tasks.Task OnWriteToStreamAsync(Type type, object value, System.IO.Stream stream, System.Net.Http.Headers.HttpContentHeaders contentHeaders, FormatterContext formatterContext, System.Net.TransportContext transportContext) { var task = Task.Factory.StartNew( () = { var settings = new JsonSerializerSettings() { NullValueHandling = NullValueHandling.Ignore, }; string json = JsonConvert.SerializeObject(value, Formatting.Indented, new JsonConverter[1] { new IsoDateTimeConverter() } ); byte[] buf = System.Text.Encoding.Default.GetBytes(json); stream.Write(buf,0,buf.Length); stream.Flush(); }); return task; } } } #endif   One advantage of the Json.NET serializer is that you can specify a few options on how things are formatted and handled. You get null value handling and you can plug in the IsoDateTimeConverter which is nice to product proper ISO dates that I would expect any Json serializer to output these days. Hooking up the Formatters Once you've created the custom formatters you need to enable them for your Web API application. To do this use the GlobalConfiguration.Configuration object and add the formatter to the Formatters collection. Here's what this looks like hooked up from Application_Start in a Web project:protected void Application_Start(object sender, EventArgs e) { // Action based routing (used for RPC calls) RouteTable.Routes.MapHttpRoute( name: "StockApi", routeTemplate: "stocks/{action}/{symbol}", defaults: new { symbol = RouteParameter.Optional, controller = "StockApi" } ); // WebApi Configuration to hook up formatters and message handlers // optional RegisterApis(GlobalConfiguration.Configuration); } public static void RegisterApis(HttpConfiguration config) { // Add JavaScriptSerializer formatter instead - add at top to make default //config.Formatters.Insert(0, new JavaScriptSerializerFormatter()); // Add Json.net formatter - add at the top so it fires first! // This leaves the old one in place so JsonValue/JsonObject/JsonArray still are handled config.Formatters.Insert(0, new JsonNetFormatter()); } One thing to remember here is the GlobalConfiguration object which is Web API's static configuration instance. I think this thing is seriously misnamed given that GlobalConfiguration could stand for anything and so is hard to discover if you don't know what you're looking for. How about WebApiConfiguration or something more descriptive? Anyway, once you know what it is you can use the Formatters collection to insert your custom formatter. Note that I insert my formatter at the top of the list so it takes precedence over the default formatter. I also am not removing the old formatter because I still want JsonValue/JsonObject/JsonArray to be handled by the default serialization mechanism. Since they process in sequence and I exclude processing for these types JsonValue et al. still get properly serialized/deserialized. Summary Currently DataContractJsonSerializer in Web API is a pain, but at least we have the ability with relatively limited effort to replace the MediaTypeFormatter and plug in our own JSON serializer. This is useful for many scenarios - if you have existing client applications that used MVC JsonResult or ASP.NET AJAX results from ASMX AJAX services you can plug in the JavaScript serializer and get exactly the same serializer you used in the past so your results will be the same and don't potentially break clients. JSON serializers do vary a bit in how they serialize some of the more complex types (like Dictionaries and dates for example) and so if you're migrating it might be helpful to ensure your client code doesn't break when you switch to ASP.NET Web API. Going forward it looks like Microsoft is planning on plugging in Json.Net into Web API and make that the default. I think that's an awesome choice since Json.net has been around forever, is fast and easy to use and provides a ton of functionality as part of this great library. I just wish Microsoft would have figured this out sooner instead of now at the last minute integrating with it especially given that Json.Net has a similar set of lower level JSON objects JsonValue/JsonObject etc. which now will end up being duplicated by the native System.Json stuff. It's not like we don't already have enough confusion regarding which JSON serializer to use (JavaScriptSerializer, DataContractJsonSerializer, JsonValue/JsonObject/JsonArray and now Json.net). For years I've been using my own JSON serializer because the built in choices are both limited. However, with an official encorsement of Json.Net I'm happily moving on to use that in my applications. Let's see and hope Microsoft gets this right before ASP.NET Web API goes gold.© Rick Strahl, West Wind Technologies, 2005-2012Posted in Web Api  AJAX  ASP.NET   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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