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Label.ImageIndex Property

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Gets or sets the index value of the image displayed on the Label.

public:
 property int ImageIndex { int get(); void set(int value); };
[System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.ImageIndexConverter))]
public int ImageIndex { get; set; }
[<System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.ImageIndexConverter))>]
member this.ImageIndex : int with get, set
Public Property ImageIndex As Integer

Property Value

Int32

A zero-based index that represents the position in the ImageList control (assigned to the ImageList property) where the image is located. The default is -1.

Attributes
TypeConverterAttribute

Exceptions

ArgumentOutOfRangeException

value is less than -1.

Examples

The following code example demonstrates how to create a Label control that has a three-dimensional border and an image displayed using the ImageList and ImageIndex properties. The control also has a caption with a mnemonic character specified. The example code uses the PreferredHeight and PreferredWidth properties to properly size the Label control on the form on which it is displayed. This example requires that an ImageList has been created and named imageList1 and that it has loaded two images. The example also requires that the code is within a form that has the System.Drawing namespace added to its code.

public:
   void CreateMyLabel()
   {
      // Create an instance of a Label.
      Label^ label1 = gcnew Label;
      
      // Set the border to a three-dimensional border.
      label1->BorderStyle = System::Windows::Forms::BorderStyle::Fixed3D;
      // Set the ImageList to use for displaying an image.
      label1->ImageList = imageList1;
      // Use the second image in imageList1.
      label1->ImageIndex = 1;
      // Align the image to the top left corner.
      label1->ImageAlign = ContentAlignment::TopLeft;
      
      // Specify that the text can display mnemonic characters.
      label1->UseMnemonic = true;
      // Set the text of the control and specify a mnemonic character.
      label1->Text = "First &Name:";
      
      /* Set the size of the control based on the PreferredHeight and PreferredWidth values. */
      label1->Size = System::Drawing::Size( label1->PreferredWidth, label1->PreferredHeight );
      
      //...Code to add the control to the form...
   }

public void CreateMyLabel()
{
   // Create an instance of a Label.
   Label label1 = new Label();

   // Set the border to a three-dimensional border.
   label1.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;
   // Set the ImageList to use for displaying an image.
   label1.ImageList = imageList1;
   // Use the second image in imageList1.
   label1.ImageIndex = 1;
   // Align the image to the top left corner.
   label1.ImageAlign = ContentAlignment.TopLeft;

   // Specify that the text can display mnemonic characters.
   label1.UseMnemonic = true;
   // Set the text of the control and specify a mnemonic character.
   label1.Text = "First &Name:";
   
   /* Set the size of the control based on the PreferredHeight and PreferredWidth values. */
   label1.Size = new Size (label1.PreferredWidth, label1.PreferredHeight);

   //...Code to add the control to the form...
}

Public Sub CreateMyLabel()
    ' Create an instance of a Label.
    Dim label1 As New Label()
       
    ' Set the border to a three-dimensional border.
    label1.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D
    ' Set the ImageList to use for displaying an image.
    label1.ImageList = imageList1
    ' Use the second image in imageList1.
    label1.ImageIndex = 1
    ' Align the image to the top left corner.
    label1.ImageAlign = ContentAlignment.TopLeft
     
    ' Specify that the text can display mnemonic characters.
    label1.UseMnemonic = True
    ' Set the text of the control and specify a mnemonic character.
    label1.Text = "First &Name:"
       
    ' Set the size of the control based on the PreferredHeight and PreferredWidth values. 
    label1.Size = New Size(label1.PreferredWidth, label1.PreferredHeight)

    '...Code to add the control to the form...
End Sub

Remarks

The ImageIndex and the ImageList properties cannot be used at the same time as the Image property. When the ImageIndex property and ImageList properties are used to display an image, the Image property is automatically set to null.

ImageKey and ImageIndex are mutually exclusive, meaning if one is set, the other is set to an invalid value and ignored. If you set the ImageKey property, the ImageIndex property is automatically set to -1. Alternatively, if you set the ImageIndex property, the ImageKey is automatically set to an empty string ("").

If the ImageList property value is changed to null, the ImageIndex property returns its default value, -1. However, the assigned ImageIndex value is retained internally and used when another ImageList object is assigned to the ImageList property. If the new ImageList assigned to the ImageList property has an ImageList.ImageCollection.Count property value that is less than or equal to the value assigned to the ImageIndex property minus one (to account for the collection being a zero-based index), the ImageIndex property value is adjusted to one less than the Count property value. For example, consider a button control whose ImageList has three images and whose ImageIndex property is set to 2. If a new ImageList that has only two images is assigned to the button, the ImageIndex value changes to 1.

Applies to

See also