C＃：如何避免在双击事件上发生TreeNode检查 [英] C#: How to avoid TreeNode check from happening on a double click event

问题描述

所以我在C＃Windows窗体应用程序中有一个TreeView。我需要的是一些节点被锁定，以便基于参数无法对其进行检查（或取消检查）。

So I have a TreeView in a C# windows form app. What I need is for some nodes to be "locked" so that they cannot be checked (or unchecked), based on a parameter.

我现在正在做的是这个：

What I am doing now is this:

private void tv_local_BeforeCheck(object sender, TreeViewCancelEventArgs e) {
    TNode node = (TNode)e.Node;
    //if a part node, cancel the action.
    if (node.Type == "Part") {
        e.Cancel = true;     
    }
    //if a locked node, cancel the action
    if (node.Locked == true) {
        e.Cancel = true;
    }
}

此代码在单击复选框时效果很好，但是如果用户双击复选框，它仍会选中/取消选中。

This code works great on a single click of the checkbox, but if the user double clicks on a checkbox, it still checks/unchecks.

我尝试过使用nodeMouseDoubleClick事件，但这并没有真正的帮助，因为我无法取消该事件...

I have tried playing with the nodeMouseDoubleClick event, but that doesnt really help, since I cannot cancel the event...

是否有任何想法可以取消节点上的双击事件？...或其他？
谢谢

Is there any ideas out there how to cancel a double click event on a node?... or anything else? Thanks

推荐答案

我认为这是TreeView中的错误（ http://social.msdn.microsoft.com/Forums/zh-美国/ winforms / thread / 9d717ce0-ec6b-4758-a357-6bb55591f956 / ）。您需要对树视图进行子类化并禁用双击消息才能对其进行修复。像这样：

This is a bug in the TreeView I think (http://social.msdn.microsoft.com/Forums/en-US/winforms/thread/9d717ce0-ec6b-4758-a357-6bb55591f956/). You need to subclass the tree view and disable the double-click message in order to fix it. Like this:

public class NoClickTree : TreeView
    {
        protected override void WndProc(ref Message m)
        {
            // Suppress WM_LBUTTONDBLCLK
            if (m.Msg == 0x203) { m.Result = IntPtr.Zero; }
            else base.WndProc(ref m);
        }              
    };

当然，如果这样做，您将不再能够使用双击隐喻在树视图中查看其他内容（例如，双击节点以启动属性页等）。

Of course if you do this you'll no longer be able to use the double-click metaphor in the tree-view for other things (such as double click a node to launch a property page, or something).

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