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I want to know how to identify a whole string if it is a Number, instead of each digit (using the index).


string number = "-1.234";

char.IsNumber( number, 0 ); //Output = FALSE

Because the - is not a number, but if I check it as a whole number then it will be TRUE...

Any other way to do not use the index?

Could you use Decimal.TryParse?
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jalmonte 8-Oct-10 11:14am    
Like, double.TryParse(number, but what I put here if just want to see if is True or False )
Marc A. Brown 8-Oct-10 11:17am    
You mean for the second (out) parameter? Create a variable of type double and pass it. If you don't need to know what the value is, just ignore the value of that variable after the call to TryParse. Make sense?
I think, you want like this
string number = "-1.234";
            double test = 0;

            if (double.TryParse(number,out test) && test >= 0)
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Dalek Dave 8-Oct-10 16:15pm    
Good Answer
shakil0304003 9-Oct-10 2:59am    
Look at the Int32.TryParse Method[^] and Double.TryParse Method[^]: they returns true if the string content represents an int or a double respectively, and false otherwise.
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You can also write an extension method that uses TryParse.
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You can use a regular expression
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