TreeView Image & Config Properties

TreeView — Image Customization & Configuration

These properties control the expand/collapse icon images, tooltip text, and data-binding configuration of the TreeView component.

Custom Expand / Collapse Images with Tooltips

Use CollapseImageUrl, ExpandImageUrl, and NoExpandImageUrl to replace the default +/- icons. Tooltips are provided via CollapseImageToolTip and ExpandImageToolTip.

<TreeView CollapseImageUrl="/img/collapse.png"
          CollapseImageToolTip="Click to collapse"
          ExpandImageUrl="/img/expand.png"
          ExpandImageToolTip="Click to expand"
          NoExpandImageUrl="/img/leaf.png">
    <Nodes>
        <TreeNode Text="Documents" Value="docs" Expanded="true">
            <TreeNode Text="Reports" Value="reports">
                <TreeNode Text="Q1 Report" Value="q1" />
            </TreeNode>
        </TreeNode>
    </Nodes>
</TreeView>

MaxDataBindDepth

MaxDataBindDepth limits how many levels of a data source are bound to the tree. The default is -1 (bind all levels). Setting it to 2 restricts binding to 2 levels deep.

Level 0

Level 1-A

Level 2-A1 (visible)

Level 3 (would be hidden by MaxDataBindDepth when data-bound)

Level 1-B

<TreeView MaxDataBindDepth="2">
    <!-- Only 2 levels will be bound from a data source -->
</TreeView>

EnableClientScript & AutoGenerateDataBindings

EnableClientScript (default true) is accepted for migration compatibility with Web Forms. AutoGenerateDataBindings controls whether data bindings are automatically created when a data source is attached.

Manual Bindings

No auto-generated bindings

Client script disabled

<TreeView EnableClientScript="false" AutoGenerateDataBindings="false">
    <Nodes>
        <TreeNode Text="Manual Bindings" Value="manual" />
    </Nodes>
</TreeView>

Properties Reference

Property	Type	Default	Description
`CollapseImageUrl`	string	null	URL of the image shown on collapsible nodes
`CollapseImageToolTip`	string	null	Tooltip for the collapse image
`ExpandImageUrl`	string	null	URL of the image shown on expandable nodes
`ExpandImageToolTip`	string	null	Tooltip for the expand image
`NoExpandImageUrl`	string	null	URL of the image shown on leaf nodes (no children)
`LineImagesFolder`	string	null	Folder path containing line images for the tree
`MaxDataBindDepth`	int	-1	Maximum depth for data binding (-1 = all levels)
`AutoGenerateDataBindings`	bool	false	Whether to auto-generate data bindings from a data source
`EnableClientScript`	bool	true	Migration stub — accepted for compatibility with Web Forms