Validate Numeric TextBox Entries Asp.Net

Question

In Asp.Net or Web-Developemnt what is the best way to ValidateTextBox's on a page. The TextChange event (server side) happens after you leave the textbox which is too late. I was going to use a Double.TryParse on server side.

Answer 1

The accepted best practice is to use a Validator control.

The CompareValidator can be used to verify the Data Type by changing the "Operator" property to "DataTypeCheck".

You could also use a RegularExpressionValidator for the same effect.

If you need to do a type check and ensure the value is withing a specified range, you would use a RangeValidator.