C# | Char.ToUpperInvariant(Char) Method Last Updated : 11 Jul, 2025 Summarize Comments Improve Suggest changes Share Like Article Like Report This method is used to converts the value of a Unicode character to its uppercase equivalent using the casing rules of the invariant culture. Syntax: public static char ToUpperInvariant (char c); Here, c is the Unicode character to convert. Return Value: This method returns the uppercase equivalent of the c parameter, or the unchanged value of c, if c is already uppercase or not alphabetic. Below programs illustrate the use of Char.ToUpperInvariant(Char) Method: Example 1: csharp // C# program to demonstrate // Char.ToUpperInvariant() // Method using System; class GFG { // Main Method public static void Main() { // calling get() Method get('A'); get('a'); get('B'); get('b'); get('-'); } // Defining get() method public static void get(char c) { // getting Unicode character // using ToUpperInvariant() Method char val = Char.ToUpperInvariant(c); // display the char value Console.WriteLine("The uppercase equivalent"+ " of the {0} is {1}", c, val); } } Output: The uppercase equivalent of the A is A The uppercase equivalent of the a is A The uppercase equivalent of the B is B The uppercase equivalent of the b is B The uppercase equivalent of the - is - Example 2: csharp // C# program to demonstrate // Char.ToUpperInvariant() // Method using System; class GFG { // Main Method public static void Main() { // declaring and initializing char variable char c = 'a'; // getting Unicode character // using ToUpperInvariant() Method char val = Char.ToUpperInvariant(c); // display the char value Console.WriteLine("The Uppercase equivalent"+ " of the {0} is {1}", c, val); } } Output: The Uppercase equivalent of the a is A Reference: https://learn.microsoft.com/en-us/dotnet/api/system.char.toupperinvariant?view=netframework-4.7.2 Comment More infoAdvertise with us Next Article C# | Char.IsLower() Method R rohitprasad3 Follow Improve Article Tags : C# CSharp-method CSharp-Char-Struct Similar Reads C# | Char.IsLetterOrDigit() Method In C#, Char.IsLetterOrDigit() is a System.Char struct method which is used to check whether a Unicode character can be categorized as a letter or decimal digit. 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