.Compare()

Published Apr 16, 2023
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The .Compare() method is a string method that compares the alphabetical order of two specified strings and returns an integer that represents their relative ranking.

Syntax

String.Compare(string1, string2, ignoreCase);
  • The .Compare() method is called on the String class. It takes two string type arguments, string1 and string2, and compares them alphabetically.
  • ignoreCase is an optional boolean type argument. By default the .Compare() method is case-sensitive. Passing true as the third argument makes the .Compare() method case-insensitive.

The .Compare() method returns an integer that represents the relative order of string1 and string2 in the alphabet:

  • -1 if string1 comes before string2
  • 0 if their position is the same (string1 and string2 are identical)
  • 1 if string2 comes before string1

Example

In the following example, the .Compare() method compares "Pizza" with "pizza" and "waffle". Then the .WriteLine() method prints the returned integer to the console:

using System;
public class Example {
public static void Main (string[] args) {
string str1 = "Pizza", str2 = "pizza", str3 = "waffle";
Console.WriteLine(String.Compare(str1, str2));
Console.WriteLine(String.Compare(str1, str3));
}
}

In the first case, "pizza" comes before "Pizza" in alphabetical order, as it is lowercase and the method is case-sensitive. In the second case, "Pizza" comes before "waffle" in alphabetical order. This example results in the following output:

1
-1

Codebyte Example

In the following runnable example, the .Compare() method determines the alphabetical order of string1 and string2, while the letter casing is ignored. Finally, the .WriteLine() method prints the returned integer to the console.

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