ListItemCollection.Clear Method

Reference

Definition

Namespace:: System.Web.UI.WebControls

Assembly:: System.Web.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Removes all ListItem objects from the collection.

public:
 virtual void Clear();

public void Clear ();

abstract member Clear : unit -> unit
override this.Clear : unit -> unit

Public Sub Clear ()

Implements

Clear()

Examples

// Copy the items in the ListItemCollection to an array before 
// deleting them.     
ListItem[] myListItemArray = new ListItem[ListBox1.Items.Count];
ListBox1.Items.CopyTo(myListItemArray, 0);

// Delete all the items from the ListBox.
ListBox1.Items.Clear();
DeleteLabel.Text = "<b>All items in the ListBox were deleted successfully." 
    + "</b><br /><b>The deleted items are:";
String listResults="";
    foreach(ListItem myItem in myListItemArray)
    {
        listResults = listResults + myItem.Text + "<br />";
    }
ResultsLabel.Text = listResults;

' Copy the items in the ListListBox1.Items to an array before 
' deleting them.     
Dim myListItemArray(ListBox1.Items.Count - 1) As ListItem
ListBox1.Items.CopyTo(myListItemArray, 0)

' Delete all the items from the ListBox.
ListBox1.Items.Clear()
DeleteLabel.Text = "<b>All items in the ListBox were deleted successfully." & _
                   "</b><br /><b>The deleted items are:"
Dim listResults As [String] = ""
Dim myItem2 As ListItem
For Each myItem2 In myListItemArray
    listResults = listResults & myItem2.Text & "<br />"
Next myItem2
ResultsLabel.Text = listResults

Remarks

Use the Clear method to remove all ListItem objects. The Count property is also set to 0.

Caution

When you use this method, all ListItem objects are removed from the collection. You cannot undo this.

Applies to

Поделиться через