C# | String.ToUpperInvariant Method Last Updated : 06 Jan, 2023 Summarize Comments Improve Suggest changes Share Like Article Like Report String.ToUpperInvariant Method is used to get a copy of this String object converted to uppercase using the casing rules of the invariant culture. Here "invariant culture" represents a culture that is culture-insensitive.Syntax: public string ToUpperInvariant (); Return Value: The return type of this method is System.String. This method will return a string which is the uppercase equivalent of the current string.Below given are some examples to understand the implementation in a better way: Example 1: CSharp // C# program to illustrate // ToUpperInvariant() method using System; public class GFG { // Main method static public void Main() { // variables string strA = "WelCome tO GeeKSfOrGeeKs"; string strB; // Convert strA into lowercase // using ToLowerInvariant() method strB = strA.ToUpperInvariant(); // Display string before ToUpperInvariant() method Console.WriteLine("String before ToUpperInvariant:"); Console.WriteLine(strA); Console.WriteLine(); // Display string after ToUpperInvariant() method Console.WriteLine("String after ToUpperInvariant:"); Console.WriteLine(strB); } } Output: String before ToUpperInvariant: WelCome tO GeeKSfOrGeeKs String after ToUpperInvariant: WELCOME TO GEEKSFORGEEKS Example 2: CSharp // C# program to illustrate // ToUpperInvariant() Method using System; public class GFG { // Main method static public void Main() { // Calling function Convert("GEeks"); Convert("geeks"); Convert("GEEKS"); } static void Convert(String value) { // Display strings Console.WriteLine("string 1: {0}", value); // Convert string into Uppercase // using ToUpperInvariant() method value = value.ToUpperInvariant(); // Display the Lowercase strings Console.WriteLine("string 2: {0}", value); } } Output: string 1: GEeks string 2: GEEKS string 1: geeks string 2: GEEKS string 1: GEEKS string 2: GEEKS Note: The invariant culture represents a culture that is culture-insensitive. It is associated with the English language but not with a specific country or region.ToUpperInvariant() method does not modify the value of the current instance. Instead, it returns a new string in which all characters in the current instance are converted to uppercase.This method can't be overloaded if you try to overload this method, it will give you compile time error. Reference: https://docs.microsoft.com/en-us/dotnet/api/system.string.toupperinvariant?view=netframework-4.7.2 Comment More infoAdvertise with us Next Article C# | String.ToLowerInvariant Method A ankita_saini Follow Improve Article Tags : C# CSharp-method CSharp-string Similar Reads C# | String.ToLowerInvariant Method String.ToLowerInvariant Method is used to get a copy of this String object converted to lowercase using the casing rules of the invariant culture. Here, "invariant culture" represents a culture that is culture-insensitive. Syntax: public string ToLowerInvariant (); Return value: The return type of t 2 min read C# String ToUpper() Method In C#, the ToUpper() method is used to convert all characters in a string to uppercase. If a character has an uppercase letter, it is converted, otherwise, it remains unchanged. Special characters and symbols are unaffected. This method is commonly used for case-insensitive comparisons and text form 2 min read C# | Char.ToUpperInvariant(Char) Method 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 2 min read C# String ToLower() Method In C#, the ToLower() method is a string method used to convert all uppercase characters in a string to lowercase. If a character does not have a lowercase equivalent, such as a special symbol, it remains unchanged. This method is particularly useful when performing case-insensitive string comparison 3 min read C# | Char.ToLowerInvariant(Char) Method This method is used to converts the value of a Unicode character to its lowercase equivalent using the casing rules of the invariant culture. Syntax: public static char ToLowerInvariant (char c); Here, c is the Unicode character to convert. Return Value: This method returns the lowercase equivalent 2 min read C# | Substring() Method In C#, Substring() is a string method. It is used to retrieve a substring from the current instance of the string. This method can be overloaded by passing the different number of parameters to it as follows: String.Substring(Int32) Method String.Substring(Int32, Int32) Method String.Substring Metho 3 min read Like