如何更改CheckedListBox项目的垂直空间

Question

我需要更改CheckedListBox项的垂直空间，以便它们适合另一侧的文本框：

这个怎么做 ？

在做了一些研究之后我发现CheckedListBox继承了ListBox ，所以它必须有它的公共属性ItemHeight ，但由于某种原因它不会

我试过这个：

ListBox l = CheckedList as ListBox;
        l.ItemHeight = 30;

但它不起作用

Answer 1

CheckedListBox的ItemHeight属性的默认实现是，

public override int ItemHeight { 
        get {
            // this should take FontHeight + buffer into Consideration.
            return Font.Height + 2;
        } 
        set {
        } 
    } 

您可以在新类中干净地覆盖此属性。

public sealed class  MyListBox:CheckedListBox
    {
        public MyListBox()
        {
            ItemHeight = 30;
        }
        public override int ItemHeight { get; set; }
    }

这应该允许您设置自己的ItemHeight。

Answer 2

这工作在VS2013网络FrameWork4.5代码是VB

将declare和constant放在类的顶部

用法将其余代码放在Form_Load中，如示例代码中所示。

Private Declare Function SendMessageByNum Lib "user32" Alias "SendMessageA" _
  (ByVal hwnd As IntPtr, ByVal wMsg As UInt32, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr

Private Const lB_SETITEMHEIGHT As Integer = &H1A0

Private Sub Form_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    Dim ItemHeight As Integer = Me.Font.Height + 4
    SendMessageByNum(CheckedListBoxControl.Handle, lB_SETITEMHEIGHT, CType(0, IntPtr), CType(ItemHeight, IntPtr))

End Sub