C# | Check if the specified string is in the StringCollection

Last Updated : 01 Feb, 2019

StringCollection class is a new addition to the .NET Framework class library that represents a collection of strings. StringCollection class is defined in the System.Collections.Specialized namespace.

StringCollection.Contains(String) method is used to check whether the specified string is in the StringCollection or not.

Syntax:

public bool Contains (string value);

Here, value is the string to locate in the StringCollection. The value can be null.

Return Value: This method returns true if value is found in the StringCollection, otherwise it returns false.

Note:

The Contains method can confirm the existence of a string before performing further operations.
This method performs a linear search, therefore, this method is an O(n) operation, where n is Count.

Below programs illustrate the use of StringCollection.Contains(String) Method:

Example 1 :

// C# code to check if the specified 
// string is in the StringCollection 
using System; 
using System.Collections; 
using System.Collections.Specialized; 
  
class GFG { 
  
    // Driver code 
    public static void Main() 
    { 
  
        // creating a StringCollection named myCol 
        StringCollection myCol = new StringCollection(); 
  
        // creating a string array named myArr 
        String[] myArr = new String[] { "A", "B", "C", "D", "E" }; 
  
        // Copying the elements of a string 
        // array to the end of the StringCollection. 
        myCol.AddRange(myArr); 
  
        // checking if StringCollection 
        // Contains "A" 
        Console.WriteLine(myCol.Contains("A")); 
    } 
} 

Output:

True

Example 2:

// C# code to check if the specified 
// string is in the StringCollection 
using System; 
using System.Collections; 
using System.Collections.Specialized; 
  
class GFG { 
  
    // Driver code 
    public static void Main() 
    { 
  
        // creating a StringCollection named myCol 
        StringCollection myCol = new StringCollection(); 
  
        // creating a string array named myArr 
        String[] myArr = new String[] { "2", "3", "4", "5", "6" }; 
  
        // Copying the elements of a string 
        // array to the end of the StringCollection. 
        myCol.AddRange(myArr); 
  
        // checking if StringCollection 
        // Contains "8" 
        Console.WriteLine(myCol.Contains("8")); 
    } 
} 