Validate TextBox For Digits, Alphabets, AlphaNumeric Characters

September 06, 2013 // In: C#

In this tutorial, I’ll show you how to validate TextBox for Alphabets, Numbers or AlphaNumeric Values. If a TextBox is validated only for Numeric, It should not accept other characters. If ¬†its validated for alphabets it should not accept other characters. Its better to make methods for validation.

validate textbox in c sharp

TextBox can be validated for Alphabets, Numbers and Alphanumeric characters via two methods. (I know there are plenty of methods, but two methods are commonly used)

Method 1

In Method 1 each character is scanned via foreach loop, if it finds any other character it stops looping and returns false.

AlphaNumeric

Digits

Alphabets

 Method 2

In Method 2, Regular Expression is used for validation. Namespace that will be used is

Alphabets

Digits

AlphaNumeric

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