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我有一个 linq 对象，我正在尝试使用 c# winforms 填充树视图。

样本

Column 1   Column 2   Column 3        
Test 1     Item A     Sub Item 1      
Test 1     Item A     Sub Item 2      
Test 1     Item A     Sub Item 3      
Test 1     Item B     Sub Item 1      
Test 1     Item B     Sub Item 2     
Test 1     Item B     Sub Item 3

并像填充树视图

Test 1 (CheckBox)
------Item A (CheckBox)
-------------Sub Item 1  (CheckBox)
-------------Sub Item 2  (CheckBox)
-------------Sub Item 3  (CheckBox)
------Item B (CheckBox)
-------------Sub Item 1  (CheckBox)
-------------Sub Item 2  (CheckBox)
-------------Sub Item 3  (CheckBox)

实现这一目标的最简单方法是什么？

谢谢Sp

4

1 回答 1

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Well, if you perform the following query:

var query = data.GroupBy(item => item.Column1)
                .Select(group => group.GroupBy(item => item.Column2))
                .Select(group => group.Select(innerGroup => 
                    innerGroup.GroupBy(item => item.Column3)));

You will have all of the items grouped first by column1, then 2 and 3, so It's already in a tree structure. Now you just need to have 3 nested for loops to add the items to the treeview.

foreach (var outermostGroup in query)
{
    //add node for outermostGroup's key
    foreach (var middleGroup in outermostGroup)
    {
        //add child node of the above node for middleGroup key
        foreach (var innerGroup in middleGroup)
        {
            //add child node of the above node for innerGroup key
        }
    }
}

Clearly this code only works if there are a fixed number of columns with a fixed (max) depth. If you don't know the number of columns and can have an arbitrary depth then you'd need a fairly radically different approach.

于 2012-08-17T13:49:32.713 回答