c# code to check whether a string is numeric or not

Question

I am using Visual Studio 2010.I want to check whether a string is numeric or not.Is there any built in function to check this or do we need to write a custom code?

Answer 1

You could use the int.TryParse method. Example:

string s = ...
int result;
if (int.TryParse(s, out result))
{
    // The string was a valid integer => use result here
}
else
{
    // invalid integer
}

There are also the float.TryParse, double.TryParse and decimal.TryParse methods for other numeric types than integers.

But if this is for validation purposes you might also consider using the built-in Validation controls in ASP.NET. Here's an example.

Answer 2

You can do like...

 string s = "sdf34";
    Int32 a;
    if (Int32.TryParse(s, out a))
    {
        // Value is numberic
    }  
    else
    {
       //Not a valid number
    }