Determines whether a string is a number.

To determine whether a string is a number or not:

1. The simplest method

Public bool isnumber (string Str) {int number = 0; return Int. tryparse (STR, out number );}

This method is applicable to most situations in daily life. However, in extreme cases, for example, if the maximum value of Int. maxvalue (2147483647) is exceeded, it will fail.

2. 10 thousand foolproof Methods

Public static bool isnumber (string numerictext) {bool isnumber = false; foreach (char C in numerictext) {isnumber = Char. isnumber (c); If (! Isnumber) {return isnumber ;}

This method is not very efficient and requires traversing strings.

3. Powerful Regular Expression matching
Regular Expressions are generated for matching verification.

Public static bool isnumber (string text) {RegEx = new RegEx (@ "^ [-+]? [0-9] * \.? [0-9] + $ "); Return RegEx. ismatch (text );}