I have here a string(an input from the user) for a file path. I checked the string so that it will qualify the criteria: check for invalid characters for a file path will not accept absolute path (\Sample\text.txt) I have tried catching the invalid characters in catch clause. It work except for '\'. It will accept 'C:\\Sample\text.txt' which is an invalid file path. The following examples should be invalid paths: :\text.txt :text.txt \:text.txt \text.txt C:\\\text.txt I have been through similar questions posted here but none of them seemed to solve my issue. What would be the best way to do such check?