#ERRORPROVIDER CONTROL CODE#

The code validates this text box using a regular expression with checks to see if the value corresponds to a valid e-mail address. The following form code checks the content of the text box every time a key is pressed. To add the ErrorProvider, drag it into the component tray or create it manually in code. You only need to add one ErrorProvider control to your form, and you can use it to display an error icon next to any control. Below figure shows how the ErrorProvider will indicate an input error for a TextBox control. When the user hovers the mouse above the warning icon, the detailed message appears. The ErrorProvider will then show a warning icon automatically to the right of the control. You show the error icon next to a control by using the ErrorProvider.SetError method and specifying the appropriate control and a string error message.

The ErrorProvider is a special provider control that displays error icons next to invalid controls. A less invasive approach is to simply flag the offending control in some way so that the user can review all the errors at once. One approach is to respond to control validation events and prevent users from changing focus from one control to another if an error exists. There are a number of ways that you can perform validation in a Windows- based application.

Errorprovider control