protected internal override void OnPreRender (EventArgs e)
{
base.OnPreRender (e);
Page page = Page;
if (page != null) {
if (IsEnabled)
page.RegisterRequiresPostBack (this);
if (EnableClientScript && !page.ClientScript.IsClientScriptIncludeRegistered (typeof(TreeView), "TreeView.js")) {
string url = page.ClientScript.GetWebResourceUrl (typeof(TreeView), "TreeView.js");
page.ClientScript.RegisterClientScriptInclude (typeof(TreeView), "TreeView.js", url);
}
}
string ctree = ClientID + "_data";
StringBuilder script = new StringBuilder ();
script.AppendFormat (_OnPreRender_Script_Preamble,
ctree,
ClientScriptManager.GetScriptLiteral (ClientID),
ClientScriptManager.GetScriptLiteral (UniqueID),
ClientScriptManager.GetScriptLiteral (ShowExpandCollapse));
if (ShowExpandCollapse) {
ImageStyle imageStyle = GetImageStyle ();
script.AppendFormat (_OnPreRender_Script_ShowExpandCollapse,
ctree,
ClientScriptManager.GetScriptLiteral (GetNodeImageUrl ("plus", imageStyle)),
ClientScriptManager.GetScriptLiteral (GetNodeImageUrl ("minus", imageStyle)));
if (PopulateNodesFromClient)
script.AppendFormat (_OnPreRender_Script_ShowExpandCollapse_Populate,
ctree,
ClientScriptManager.GetScriptLiteral (GetNodeImageUrl ("noexpand", imageStyle)));
}
if (page != null) {
script.AppendFormat (_OnPreRender_Script_PopulateCallback,
ctree,
page.theForm,
page.WebFormScriptReference);
// Page.ClientScript.GetCallbackEventReference (
// "this.uid", "nodeId",
// "TreeView_PopulateCallback",
// "this.treeId + \" \" + nodeId", "TreeView_PopulateCallback", false));
script.AppendFormat (_OnPreRender_Script_CallbackOptions,
ctree,
ClientScriptManager.GetScriptLiteral (PopulateNodesFromClient),
ClientScriptManager.GetScriptLiteral (GetNodeImageToolTip (true, null)),
ClientScriptManager.GetScriptLiteral (GetNodeImageToolTip (false, null)));
if (!page.IsPostBack)
SetNodesExpandedToDepthRecursive (Nodes);
bool enableClientScript = EnableClientScript;
if (enableClientScript) {
page.ClientScript.RegisterHiddenField (ClientID + "_ExpandStates", GetExpandStates ());
// Make sure the basic script infrastructure is rendered
page.ClientScript.RegisterWebFormClientScript ();
}
if (enableClientScript && PopulateNodesFromClient)
page.ClientScript.RegisterHiddenField (ClientID + "_PopulatedStates", "|");
EnsureStylesPrepared ();
if (hoverNodeStyle != null) {
if (page.Header == null)
throw new InvalidOperationException ("Using TreeView.HoverNodeStyle requires Page.Header to be non-null (e.g. <head runat=\"server\" />).");
RegisterStyle (HoverNodeStyle, HoverNodeLinkStyle);
script.AppendFormat (_OnPreRender_Script_HoverStyle,
ctree,
ClientScriptManager.GetScriptLiteral (HoverNodeStyle.RegisteredCssClass),
ClientScriptManager.GetScriptLiteral (HoverNodeLinkStyle.RegisteredCssClass));
}
page.ClientScript.RegisterStartupScript (typeof(TreeView), this.UniqueID, script.ToString (), true);
script = null;
}
}
