method ChartView.BeginUpdate ()
Maintains performance when items are added to the control one at a time.

 TypeDescription 

The BeginUpdate method prevents the control from painting until the EndUpdate method is called. Use the Add method to add new child nodes. Use the Remove method to remove a node from the control. Use the Root property to get the root node of the control.

The following VB sample adds four nodes to the control :

With ChartView1
    .BeginUpdate
    With .Nodes
        .Add "Item 1", "root", "Key1"
        .Add "Item 2", "root"
        .Add "Sub Item 1", "Key1"
        .Add "Sub Item 2", "Key1"
    End With
    .EndUpdate
End With

The following C++ sample adds four nodes to the control :

#include "nodes.h"
COleVariant vtMissing; V_VT( &vtMissing ) = VT_ERROR;
m_chartview.BeginUpdate();
CNodes nodes = m_chartview.GetNodes();
nodes.Add( "Item 1", COleVariant( "root" ), COleVariant("Key1"), vtMissing, vtMissing );
nodes.Add( "Item 2", COleVariant( "root" ), vtMissing, vtMissing, vtMissing );
nodes.Add( "Sub Item 1", COleVariant( "Key1" ), vtMissing, vtMissing, vtMissing );
nodes.Add( "Sub Item 2", COleVariant( "Key1" ), vtMissing, vtMissing, vtMissing );
m_chartview.EndUpdate();

The following VB.NET sample adds four nodes to the control :

With AxChartView1
    .BeginUpdate()
    With .Nodes
        .Add("Item 1", "root", "Key1")
        .Add("Item 2", "root")
        .Add("Sub Item 1", "Key1")
        .Add("Sub Item 2", "Key1")
    End With
    .EndUpdate()
End With

The following C# sample adds four nodes to the control :

axChartView1.BeginUpdate();
EXORGCHARTLib.Nodes nodes = axChartView1.Nodes;
nodes.Add("Item 1", "root", "Key1", null, null);
nodes.Add("Item 2", "root", null, null, null);
nodes.Add("Sub Item 1", "Key1", null, null, null);
nodes.Add("Sub Item 2", "Key1", null, null, null);
axChartView1.EndUpdate();

The following VFP sample adds four nodes to the control :

With thisform.ChartView1
    .BeginUpdate
    With .Nodes
        .Add("Item 1", "root", "Key1")
        .Add("Item 2", "root")
        .Add("Sub Item 1", "Key1")
        .Add("Sub Item 2", "Key1")
    EndWith
    .EndUpdate
EndWith

 

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