What is Char.IsNumber() in C#?
Overview
Char.IsNumber() is a C# method that is used to check whether a certain character or character in a string at a specified position is categorized as a number or not.
If it is a number, then a Boolean True value is returned. If it is not a number, then a False value is returned.
Syntax
// for a character
IsNumber(Char)
// for a string
IsNumber(String, Int32)
Parameters
Char: This is the character we want to check to see if it is a number.
String: This is the string that contains the character we want to check. We specify the character in this string by using its index position in the string.
Int32: This represents the index position of a character in a string.
Returned value
The value returned is a Boolean value. It returns True if the character is a number. Conversely, it returns False if the character is not a number.
Code
In the following example, we will demonstrate the use of the Char.IsNumber() method. We will create some characters and strings, and check if any of the characters are numbers or not.
// use Systemusing System;// create a classclass NumberChecker{// main methodstatic void Main(){// create some characterschar ch1 = 'h';char ch2 = '#';char ch3 = '5';// create some stringsstring s1 = "Hi, 1234!";string s2 = "whatever";// check if characters are numbersbool a = Char.IsNumber(ch1);bool b = Char.IsNumber(ch2);bool c = Char.IsNumber(ch3);bool d = Char.IsNumber(s1, 5); // sixth positionbool e = Char.IsNumber(s2, 2); // third position// print returned valuesConsole.WriteLine(a);Console.WriteLine(b);Console.WriteLine(c);Console.WriteLine(d);Console.WriteLine(e);}}
Explanation
In the code above, we can see that:
- Only
ch3, which is'5', and the character at the sixth position ins1, which is3, are numbers. This is why they returnedTrue. - The rest all returned
False, because they are not numbers.
