Question

How to validate a mobile number textbox and email textbox using regular expressions in C#?

I want to validate these first at the front end itself so that the database doesn’t receive any invalid input or rather even checks for it.

I am using Windows Forms.

Answer 1

You can use System.Text.RegularExpression

I’ll give you an example for e-mail validation

then declare a regular expression like

Regex myRegularExpression = new 
                            Regex(" \b[A-Z0-9._%-]+@[A-Z0-9.-]+\.[A-Z]{2,4}\b");

and say your e-mail textbox is txtEmail

then write,

   if(myRegularExpression.isMatch(txtEmail.Text))
   {
        //valid e-mail
   }

Update

Not an expert on regular expressions,

Here’s the link to Regular expression to validate e-mail

you can find more details about the regEx from the link provided.