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String.IndexOf Method (String)

.NET Framework 1.1

Reports the index of the first occurrence of the specified String in this instance.

[Visual Basic]
Overloads Public Function IndexOf( _
   ByVal value As String _
) As Integer
[C#]
public int IndexOf(
 string value
);
[C++]
public: int IndexOf(
 String* value
);
[JScript]
public function IndexOf(
   value : String
) : int;

Parameters

value
The String to seek.

Return Value

The index position of value if that string is found, or -1 if it is not. If value is Empty, the return value is 0.

Exceptions

Exception Type Condition
ArgumentNullException value is a null reference (Nothing in Visual Basic).

Remarks

Index numbering starts from zero.

This method performs a word (case-sensitive and culture-sensitive) search using the current culture. The search begins at the first character position of this instance and continues until the last character position.

Example

The following code exampled demonstrates the IndexOf method.

[Visual Basic] 
Imports System

Public Class InsertTest
    
    Public Shared Sub Main()
        Dim animal1 As String = "fox"
        Dim animal2 As String = "dog"
        Dim strTarget As String = [String].Format("The {0} jumped over the {1}.", animal1, animal2)
        
        Console.WriteLine("The original string is:{0}{1}{0}", Environment.NewLine, strTarget)
        
        Console.Write("Please enter an adjective (or a group of adjectives) to describe the {0}: ==> ", animal1)
        Dim adj1 As String = Console.ReadLine()
        
        Console.Write("Please enter an adjective (or a group of adjectives) to describe the {0}: ==> ", animal2)
        Dim adj2 As String = Console.ReadLine()
        
        adj1 = adj1.Trim() + " "
        adj2 = adj2.Trim() + " "
        
        strTarget = strTarget.Insert(strTarget.IndexOf(animal1), adj1)
        strTarget = strTarget.Insert(strTarget.IndexOf(animal2), adj2)
        
        Console.WriteLine("{0}The final string is:{0}{1}", Environment.NewLine, strTarget)
    End Sub 'Main
End Class 'InsertTest

[C#] 
using System;

public class InsertTest {
    public static void Main() {

        string animal1 = "fox";
        string animal2 = "dog";

        string strTarget = String.Format("The {0} jumped over the {1}.", animal1, animal2);

        Console.WriteLine("The original string is:{0}{1}{0}", Environment.NewLine, strTarget);

        Console.Write("Please enter an adjective (or a group of adjectives) to describe the {0}: ==> ", animal1);
        string adj1 = Console.ReadLine();

        Console.Write("Please enter an adjective (or a group of adjectives) to describe the {0}: ==> ", animal2);    
        string adj2 = Console.ReadLine();

        adj1 = adj1.Trim() + " ";
        adj2 = adj2.Trim() + " ";

        strTarget = strTarget.Insert(strTarget.IndexOf(animal1), adj1);
        strTarget = strTarget.Insert(strTarget.IndexOf(animal2), adj2);

        Console.WriteLine("{0}The final string is:{0}{1}", Environment.NewLine, strTarget);
    }
}

[C++] 
#using <mscorlib.dll>

using namespace System;
int main()
{
   String* animal1 = S"fox";
   String* animal2 = S"dog";

   String* strTarget = String::Format(S"The {0} jumped over the {1}.", animal1, animal2);

   Console::WriteLine(S"The original string is:{0}{1}{0}", Environment::NewLine, strTarget);

   Console::Write(S"Please enter an adjective (or a group of adjectives) to describe the {0}: ==> ", animal1);
   String* adj1 = Console::ReadLine();

   Console::Write(S"Please enter an adjective (or a group of adjectives) to describe the {0}: ==> ", animal2);    
   String* adj2 = Console::ReadLine();

   adj1 = String::Concat( adj1->Trim(), S" ");
   adj2 = String::Concat( adj2->Trim(), S" ");

   strTarget = strTarget->Insert(strTarget->IndexOf(animal1), adj1);
   strTarget = strTarget->Insert(strTarget->IndexOf(animal2), adj2);

   Console::WriteLine(S" {0}The final string is: {0} {1}", Environment::NewLine, strTarget);
}

[JScript] 
import System;

public class InsertTest {
    public static function Main() : void {

        var animal1 : String = "fox";
        var animal2 : String = "dog";

        var strTarget : String = String.Format("The {0} jumped over the {1}.", animal1, animal2);

        Console.WriteLine("The original string is:{0}{1}{0}", Environment.NewLine, strTarget);

        Console.Write("Please enter an adjective (or a group of adjectives) to describe the {0}: ==> ", animal1);
        var adj1 : String = Console.ReadLine();

        Console.Write("Please enter an adjective (or a group of adjectives) to describe the {0}: ==> ", animal2);    
        var adj2 : String = Console.ReadLine();

        adj1 = adj1.Trim() + " ";
        adj2 = adj2.Trim() + " ";

        strTarget = strTarget.Insert(strTarget.IndexOf(animal1), adj1);
        strTarget = strTarget.Insert(strTarget.IndexOf(animal2), adj2);

        Console.WriteLine("{0}The final string is:{0}{1}", Environment.NewLine, strTarget);
    }
}
InsertTest.Main();

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework, Common Language Infrastructure (CLI) Standard

See Also

String Class | String Members | System Namespace | String.IndexOf Overload List | Int32 | CultureInfo | IndexOfAny | LastIndexOf | LastIndexOfAny

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