Reports the index of the first occurrence of a String, or one or more characters, within this instance.
Overload List
Reports the index of the first occurrence of the specified Unicode character in this instance.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Function IndexOf(Char) As Integer
[C#] public int IndexOf(char);
[C++] public: int IndexOf(__wchar_t);
[JScript] public function IndexOf(Char) : int;
Reports the index of the first occurrence of the specified String in this instance.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Function IndexOf(String) As Integer
[C#] public int IndexOf(string);
[C++] public: int IndexOf(String*);
[JScript] public function IndexOf(String) : int;
Reports the index of the first occurrence of the specified Unicode character in this instance. The search starts at a specified character position.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Function IndexOf(Char, Integer) As Integer
[C#] public int IndexOf(char, int);
[C++] public: int IndexOf(__wchar_t, int);
[JScript] public function IndexOf(Char, int) : int;
Reports the index of the first occurrence of the specified String in this instance. The search starts at a specified character position.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Function IndexOf(String, Integer) As Integer
[C#] public int IndexOf(string, int);
[C++] public: int IndexOf(String*, int);
[JScript] public function IndexOf(String, int) : int;
Reports the index of the first occurrence of the specified character in this instance. The search starts at a specified character position and examines a specified number of character positions.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Function IndexOf(Char, Integer, Integer) As Integer
[C#] public int IndexOf(char, int, int);
[C++] public: int IndexOf(__wchar_t, int, int);
[JScript] public function IndexOf(Char, int, int) : int;
Reports the index of the first occurrence of the specified String in this instance. The search starts at a specified character position and examines a specified number of character positions.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Function IndexOf(String, Integer, Integer) As Integer
[C#] public int IndexOf(string, int, int);
[C++] public: int IndexOf(String*, int, int);
[JScript] public function IndexOf(String, int, int) : int;
Example
[Visual Basic, C#, C++] Note This example shows how to use one of the overloaded versions of IndexOf. For other examples that might be available, see the individual overload topics.
[Visual Basic]
' Sample for String.IndexOf(String, Int32, Int32)
Imports System
Class Sample
Public Shared Sub Main()
Dim br1 As String = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-"
Dim br2 As String = "0123456789012345678901234567890123456789012345678901234567890123456"
Dim str As String = "Now is the time for all good men to come to the aid of their party."
Dim start As Integer
Dim at As Integer
Dim [end] As Integer
Dim count As Integer
[end] = str.Length
start = [end] / 2
Console.WriteLine()
Console.WriteLine("All occurrences of 'he' from position {0} to {1}.", start, [end] - 1)
Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str)
Console.Write("The string 'he' occurs at position(s): ")
count = 0
at = 0
While start <= [end] AndAlso at > - 1
' start+count must be a position within -str-.
count = [end] - start
at = str.IndexOf("he", start, count)
If at = - 1 Then
Exit While
End If
Console.Write("{0} ", at)
start = at + 1
End While
Console.WriteLine()
End Sub 'Main
End Class 'Sample
'
'This example produces the following results:
'
'All occurrences of 'he' from position 33 to 66.
'0----+----1----+----2----+----3----+----4----+----5----+----6----+-
'0123456789012345678901234567890123456789012345678901234567890123456
'Now is the time for all good men to come to the aid of their party.
'
'The string 'he' occurs at position(s): 45 56
'
'
[C#]
// Sample for String.IndexOf(String, Int32, Int32)
using System;
class Sample {
public static void Main() {
string br1 = "0----+----1----+----2----+----3----+----4----+----5----+----6----+-";
string br2 = "0123456789012345678901234567890123456789012345678901234567890123456";
string str = "Now is the time for all good men to come to the aid of their party.";
int start;
int at;
int end;
int count;
end = str.Length;
start = end/2;
Console.WriteLine();
Console.WriteLine("All occurrences of 'he' from position {0} to {1}.", start, end-1);
Console.WriteLine("{1}{0}{2}{0}{3}{0}", Environment.NewLine, br1, br2, str);
Console.Write("The string 'he' occurs at position(s): ");
count = 0;
at = 0;
while((start <= end) && (at > -1))
{
// start+count must be a position within -str-.
count = end - start;
at = str.IndexOf("he", start, count);
if (at == -1) break;
Console.Write("{0} ", at);
start = at+1;
}
Console.WriteLine();
}
}
/*
This example produces the following results:
All occurrences of 'he' from position 33 to 66.
0----+----1----+----2----+----3----+----4----+----5----+----6----+-
0123456789012345678901234567890123456789012345678901234567890123456
Now is the time for all good men to come to the aid of their party.
The string 'he' occurs at position(s): 45 56
*/
[C++]
// Sample for String::IndexOf(String, Int32, Int32)
#using <mscorlib.dll>
using namespace System;
int main() {
String* br1 = S"0----+----1----+----2----+----3----+----4----+----5----+----6----+-";
String* br2 = S"0123456789012345678901234567890123456789012345678901234567890123456";
String* str = S"Now is the time for all good men to come to the aid of their party.";
int start;
int at;
int end;
int count;
end = str->Length;
start = end/2;
Console::WriteLine();
Console::WriteLine(S"All occurrences of 'he' from position {0} to {1}.", __box( start), __box( end-1));
Console::WriteLine(S"{1}{0}{2}{0}{3}{0}", Environment::NewLine, br1, br2, str);
Console::Write(S"The string 'he' occurs at position(s): ");
count = 0;
at = 0;
while((start <= end) && (at > -1)) {
// start+count must be a position within -str-.
count = end - start;
at = str->IndexOf(S"he", start, count);
if (at == -1) break;
Console::Write(S"{0} ", __box( at));
start = at+1;
}
Console::WriteLine();
}
/*
This example produces the following results:
All occurrences of 'he' from position 33 to 66.
0----+----1----+----2----+----3----+----4----+----5----+----6----+-
0123456789012345678901234567890123456789012345678901234567890123456
Now is the time for all good men to come to the aid of their party.
The string 'he' occurs at position(s): 45 56
*/
[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button .gif)
in the upper-left corner of the page.
See Also
String Class | String Members | System Namespace