The content block ID from which the server control gets the metadata. If you want to add metadata from several content blocks, set this property to 0 (zero) and use the DefaultItemList property to identify the content blocks.

[Bindable(true)]
[Category("Ektron")]
[Editor(typeof(ContentBlockUITypeEditor), typeof(System.Drawing.Design.UITypeEditor))]
[DefaultValue(0)]
[Description("Gets or Sets the Default ContentID for this Control.")]
public long DefaultContentID;

<Bindable(true)>
<Category("Ektron")>
<Editor(typeof(ContentBlockUITypeEditor), typeof(System.Drawing.Design.UITypeEditor))>
<DefaultValue(0)>
<Description("Gets or Sets the Default ContentID for this Control.")>
Public Property DefaultContentID() As long