C# | Char.IsSurrogate(String, Int32) Method
This method is used to indicates whether the character at the specified position in a specified string has a surrogate code unit or not.
Syntax:
public static bool IsSurrogate (string s, int index);
Parameters:
s: It is a String.
index: It is the character position to evaluate in s.
Return Value: This method returns true if the character at position index in s is either a high surrogate or a low surrogate otherwise, it returns false.
Exceptions:
- ArgumentNullException: If the s is null.
- ArgumentOutOfRangeException: If the index is less than zero or greater than the last position inn s.
Below programs illustrate the use of Char.IsSurrogate(String, Int32) Method:
Example 1:
// C# program to demonstrate // Char.IsSurrogate(String, // Int32) Method using System; class GFG { // Main Method public static void Main() { try { // calling check() Method check( "1234" , 3); check( "Tsunami" , 3); check( "psyc0lo" , 4); // declaring and initializing string s1 string s1 = new String( new char [] { 'a' , '\uD800' , '\uDC00' , 'z' }); check(s1, 2); } catch (ArgumentNullException e) { Console.Write( "Exception Thrown: " ); Console.Write( "{0}" , e.GetType(), e.Message); } catch (ArgumentOutOfRangeException e) { Console.Write( "Exception Thrown: " ); Console.Write( "{0}" , e.GetType(), e.Message); } } // Defining check() method public static void check( string s, int i) { // checking condition bool val = Char.IsSurrogate(s, i); // checking if (val) Console.WriteLine( "String '{0}' contains " + "Surrogate value at index {1} " ,s, i); else Console.WriteLine( "String '{0}' does't contain any" + "Surrogate value at index {1}" ,s, i); } } |
Output:
String '1234' does't contain anySurrogate value at index 3 String 'Tsunami' does't contain anySurrogate value at index 3 String 'psyc0lo' does't contain anySurrogate value at index 4 String 'að??z' contains Surrogate value at index 2
Example 2: For ArgumentNullException
// C# program to demonstrate // Char.IsSurrogate(String, // Int32) Method using System; class GFG { // Main Method public static void Main() { try { // calling check() Method check( "1234" , 3); check( "Tsunami" , 3); check( "psyc0lo" , 4); // declaring and initializing string s1 string s1 = new String( new char [] { 'a' , '\uD800' , '\uDC00' , 'z' }); check(s1, 2); Console.WriteLine( "" ); Console.WriteLine( "s is null" ); check( null , 4); } catch (ArgumentNullException e) { Console.Write( "Exception Thrown: " ); Console.Write( "{0}" , e.GetType(), e.Message); } catch (ArgumentOutOfRangeException e) { Console.Write( "Exception Thrown: " ); Console.Write( "{0}" , e.GetType(), e.Message); } } // Defining check() method public static void check( string s, int i) { // checking condition bool val = Char.IsSurrogate(s, i); // checking if (val) Console.WriteLine( "String '{0}' contains " + "Surrogate value at index {1} " ,s, i); else Console.WriteLine( "String '{0}' does't contain any" + "Surrogate value at index {1}" , s, i); } } |
Output:
String '1234' does't contain anySurrogate value at index 3 String 'Tsunami' does't contain anySurrogate value at index 3 String 'psyc0lo' does't contain anySurrogate value at index 4 String 'að??z' contains Surrogate value at index 2 s is null Exception Thrown: System.ArgumentNullException
Example 3: For ArgumentOutOfRangeException
// C# program to demonstrate // Char.IsSurrogate(String, // Int32) Method using System; class GFG { // Main Method public static void Main() { try { // calling check() Method check( "1234" , 3); check( "Tsunami" , 3); check( "psyc0lo" , 4); // declaring and initializing string s1 string s1 = new String( new char [] { 'a' , '\uD800' , '\uDC00' , 'z' }); check(s1, 2); Console.WriteLine( "" ); Console.WriteLine( "index is less than zero" ); check( "null" , -4); } catch (ArgumentNullException e) { Console.Write( "Exception Thrown: " ); Console.Write( "{0}" , e.GetType(), e.Message); } catch (ArgumentOutOfRangeException e) { Console.Write( "Exception Thrown: " ); Console.Write( "{0}" , e.GetType(), e.Message); } } // Defining check() method public static void check( string s, int i) { // checking condition bool val = Char.IsSurrogate(s, i); // checking if (val) Console.WriteLine( "String '{0}' contains " + "Surrogate value at index {1} " , s, i); else Console.WriteLine( "String '{0}' does't contain any" + "Surrogate value at index {1}" , s, i); } } |
Output:
String '1234' does't contain anySurrogate value at index 3 String 'Tsunami' does't contain anySurrogate value at index 3 String 'psyc0lo' does't contain anySurrogate value at index 4 String 'að??z' contains Surrogate value at index 2 index is less than zero Exception Thrown: System.ArgumentOutOfRangeException
Reference: