Numeric Value

Thanks everybody. The most of the solutions are similar. Regular expressions are interesting, I will use them in many others situations and I'll replace several parts of my code. Thank you. Carlos

I use this one: bool isNumber = true; try { int n = int.Parse(textBox1.Text); } catch { isNumber = false; }

hi this is " regular expression" ^ means: matches the position in the start of the string [0-9] means: match the range of numbers of the range 0:9 ........... $ means: match this at the end of the string the hole statement means match that the string characters from start till end equal to 0-9 only numbers but this way is complicated for my opinion .........use any methode other people said in the first they are enough ............... thanks

What it means "^[0-9]+$" n' what else you can do with this? Can you explain some more about it? Thanx everybody.

Also you can use regular expressions using System.Text.RegularExpressions; .... Regex expression = new Regex("^[0-9]+$"); if (expression.Match(textBox1.Text).Success == false) { MessageBox.Show("not a number!"); } -Mike G.

whoops there is an error. instead of "||" in the if statement, replace that with "&&".

A way that I usually used to see whether there letters is: private bool IsAlpha( string strToCheck ) { bool Valid = true; foreach( char c in strToCheck ) { if ( !( c >= 65 && c <= 90 ) || !( c >= 97 && c <= 122 ) ) { Valid = false; break; } } return Valid; } 65 through 90 are the ascii code for the capital letters. 97 through 122 are the ascii code for the lower case letters.

Is a good method. thanx jamesdivine.

there may be a better way, but this is what I've used in the past private bool IsNumeric(object myobject) { bool tmpbool = true; try { int tmpint = Convert.ToInt32(myobject); } catch(Exception) { tmpbool = false; } return tmpbool; }