Can someone help me with Regular Expression in .net

Question

Can someone help me modify this

[RegularExpression(@"([0-9]+)", ErrorMessage = "Must be a Number.")] 

to become like this form. Example 12345678X eight numbers and the last char is an alphabetic character.

Answer 1

I hope this will solve your issue

[Test]
public void RegexTest()
{
    var regex = new Regex("^[0-9]{8}[A-Za-z]$");
    Assert.IsTrue(regex.IsMatch("12345678A"));
    Assert.IsFalse(regex.IsMatch("12345678AB"));
}