Array.SetValue Method (Object, Int32)


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Sets a value to the element at the specified position in the one-dimensional Array. The index is specified as a 32-bit integer.

Namespace:   System
Assembly:  mscorlib (in mscorlib.dll)

public void SetValue(
	object value,
	int index


Type: System.Object

The new value for the specified element.

Type: System.Int32

A 32-bit integer that represents the position of the Array element to set.

Exception Condition

The current Array does not have exactly one dimension.


value cannot be cast to the element type of the current Array.


index is outside the range of valid indexes for the current Array.

The GetLowerBound and GetUpperBound methods can determine whether the value of index is out of bounds.

For more information about conversions, see Convert.

This method is an O(1) operation.


If SetValue is used to assign null to an element of an array of value types, all fields of the element are initialized to zero. The value of the element is not a null reference, and cannot be found by searching for a null reference.

The following code example demonstrates how to set and get a specific value in a one-dimensional or multidimensional array.

using System;

public class SamplesArray  {

   public static void Main()  {

      // Creates and initializes a one-dimensional array.
      String[] myArr1 = new String[5];

      // Sets the element at index 3.
      myArr1.SetValue( "three", 3 );
      Console.WriteLine( "[3]:   {0}", myArr1.GetValue( 3 ) );

      // Creates and initializes a two-dimensional array.
      String[,] myArr2 = new String[5,5];

      // Sets the element at index 1,3.
      myArr2.SetValue( "one-three", 1, 3 );
      Console.WriteLine( "[1,3]:   {0}", myArr2.GetValue( 1, 3 ) );

      // Creates and initializes a three-dimensional array.
      String[,,] myArr3 = new String[5,5,5];

      // Sets the element at index 1,2,3.
      myArr3.SetValue( "one-two-three", 1, 2, 3 );
      Console.WriteLine( "[1,2,3]:   {0}", myArr3.GetValue( 1, 2, 3 ) );

      // Creates and initializes a seven-dimensional array.
      String[,,,,,,] myArr7 = new String[5,5,5,5,5,5,5];

      // Sets the element at index 1,2,3,0,1,2,3.
      int[] myIndices = new int[7] { 1, 2, 3, 0, 1, 2, 3 };
      myArr7.SetValue( "one-two-three-zero-one-two-three", myIndices );
      Console.WriteLine( "[1,2,3,0,1,2,3]:   {0}", myArr7.GetValue( myIndices ) );



This code produces the following output.

[3]:   three
[1,3]:   one-three
[1,2,3]:   one-two-three
[1,2,3,0,1,2,3]:   one-two-three-zero-one-two-three


Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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