How to delete a row from a typed dataset and save it to a database?
- by Zingam
I am doing this as a small project to learn about disconnected and connected models in .NET 4.0 and SQL Server 2008 R2.
I have three tables:
Companies (PK CompanyID)
Addresses (PK AddressID, FK CompanyID)
ContactPersons (PK ContactPersonID, FK CompanyID)
CompanyID is assigned manually by the users. The other IDs are auto-generated. Companies has a one-to-many relationship with ContactPerson. I have set any changes to cascade.
I display all records in Companies in a DataGridView and when a row is clicked, the corresponding records in ContactPersons are displayed in a second DataGridView.
I have successfully implemented updating and inserting new records but I completely fail in my attempts to delete rows and save the changes to the database.
I us a typed dataset.
If I use this:
DataRow[] contactPersonRows = m_SoldaCompaniesFileDataSet.ContactPersons.Select("ContactPersonID = "
+ this.m_CurrentContactPerson.ContactPersonID);
m_SoldaCompaniesFileDataSet.ContactPersons.Rows.Remove(contactPersonRows[0]);
The records are displayed properly in the DataGridView but are not saved in the database later.
If I use this:
DataRow row = m_SoldaCompaniesFileDataSet.ContactPersons.Rows.Find(this.m_CurrentContactPerson.ContactPersonID);
row.Delete();
The records are set but I get an exeception: DeletedRowInaccessibleException, when I try to refresh the DataGridView. The exception pop-s up in the auto-generated dataset.design file.
I am pretty much stuck at this point since yesterday. I cannot find anything anywhere that remotely resembles my problem. And I cannot understand actually what is going on.
