ComboBox.ObjectCollection.AddRange(Object[]) Method

Definition

Namespace:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Source:

ComboBox.ObjectCollection.cs

Adds an array of items to the list of items for a ComboBox.

public:
 void AddRange(... cli::array <System::Object ^> ^ items);

public void AddRange (params object[] items);

member this.AddRange : obj[] -> unit

Public Sub AddRange (ParamArray items As Object())

Parameters

items

Object[]

An array of objects to add to the list.

Exceptions

ArgumentNullException

An item in the items parameter was null.

Examples

The following code example demonstrates how to initialize a ComboBox control by setting the text property and using the AddRange method to populate the ComboBox. It also demonstrates handling the DropDown event. To run the example, paste the following code in a form and call the InitializeComboBox method from the form's constructor or Load method.

internal:
   // Declare ComboBox1
   System::Windows::Forms::ComboBox^ ComboBox1;

private:
   // Initialize ComboBox1.
   void InitializeComboBox()
   {
      this->ComboBox1 = gcnew ComboBox;
      this->ComboBox1->Location = System::Drawing::Point( 128, 48 );
      this->ComboBox1->Name = "ComboBox1";
      this->ComboBox1->Size = System::Drawing::Size( 100, 21 );
      this->ComboBox1->TabIndex = 0;
      this->ComboBox1->Text = "Typical";
      array<String^>^ installs = {"Typical","Compact","Custom"};
      ComboBox1->Items->AddRange( installs );
      this->Controls->Add( this->ComboBox1 );
      
      // Hook up the event handler.
      this->ComboBox1->DropDown += gcnew System::EventHandler(
         this, &Form1::ComboBox1_DropDown );
   }

   // Handles the ComboBox1 DropDown event. If the user expands the  
   // drop-down box, a message box will appear, recommending the
   // typical installation.
   void ComboBox1_DropDown( Object^ sender, System::EventArgs^ e )
   {
      MessageBox::Show( "Typical installation is strongly recommended.",
         "Install information", MessageBoxButtons::OK,
         MessageBoxIcon::Information );
   }

// Declare ComboBox1.
internal System.Windows.Forms.ComboBox ComboBox1;

// Initialize ComboBox1.
private void InitializeComboBox()
{
    this.ComboBox1 = new ComboBox();
    this.ComboBox1.Location = new System.Drawing.Point(128, 48);
    this.ComboBox1.Name = "ComboBox1";
    this.ComboBox1.Size = new System.Drawing.Size(100, 21);
    this.ComboBox1.TabIndex = 0;
    this.ComboBox1.Text	= "Typical";
    string[] installs = new string[]{"Typical", "Compact", "Custom"};
    ComboBox1.Items.AddRange(installs);
    this.Controls.Add(this.ComboBox1);
    
    // Hook up the event handler.
    this.ComboBox1.DropDown +=  
        new System.EventHandler(ComboBox1_DropDown);
}

// Handles the ComboBox1 DropDown event. If the user expands the  
// drop-down box, a message box will appear, recommending the
// typical installation.
private void ComboBox1_DropDown(object sender, System.EventArgs e)
{
    MessageBox.Show("Typical installation is strongly recommended.", 
    "Install information", MessageBoxButtons.OK, 
        MessageBoxIcon.Information);
}

' Declare ComboBox1.
Friend WithEvents ComboBox1 As System.Windows.Forms.ComboBox

' Initialize ComboBox1.
Private Sub InitializeComboBox()
    Me.ComboBox1 = New ComboBox
    Me.ComboBox1.Location = New System.Drawing.Point(128, 48)
    Me.ComboBox1.Name = "ComboBox1"
    Me.ComboBox1.Size = New System.Drawing.Size(100, 21)
    Me.ComboBox1.TabIndex = 0
    Me.ComboBox1.Text = "Typical"
    Dim installs() As String = New String() _
        {"Typical", "Compact", "Custom"}
    ComboBox1.Items.AddRange(installs)
    Me.Controls.Add(Me.ComboBox1)
End Sub

' Handles the ComboBox1 DropDown event. If the user expands the  
' drop-down box, a message box will appear, recommending the
' typical installation.
Private Sub ComboBox1_DropDown _ 
    (ByVal sender As Object, ByVal e As System.EventArgs) _ 
    Handles ComboBox1.DropDown
    MessageBox.Show("Typical installation is strongly recommended.", _
    "Install information", MessageBoxButtons.OK, MessageBoxIcon.Information)
End Sub

Remarks

If the Sorted property of the ComboBox is set to true, the items are inserted into the list alphabetically. Otherwise, the items are inserted in the order they occur within the array. This method is typically passed an array of String objects, but an array of any type of object can be passed to this method. When an object is added to the collection, the method calls the object's ToString method to obtain the string to display in the list. When using this method to add items to the collection, you do not need to call the BeginUpdate and EndUpdate methods to optimize performance.