how to apply validation to textbox?

Question

in windows form of C# i want to apply validation how can achieve it?

Ankit Nandekar · Answer

Read this article it will help u http://www.c-sharpcorner.com/UploadFile/aa04e6/5757/

Vulpes · Answer

You can also do validation after focus has left the textbox by setting its CausesValidation property to true and then handling its Validating event. Check out the example on MSDN ( http://msdn.microsoft.com/en-us/library/system.windows.forms.control.validating.aspx ) which also uses an ErrroProvider control.

Vulpes · Answer

One thing I've never liked about character-by-character validation is that if the user pastes something in it can mess up the logic. It's possible to allow for this but it makes the code more complicated.

Sam Hobbs · Answer

I think that the advantage of doing what the  Validation Using the KeyPress Event in a Windows Application  article shows is that validation occurs as each key is pressed. If it were me I would derive a class from TextBox and do the validation in it. The advantage of CausesValidation is that it is built into controls so it will usually require less code.