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c#winformsclasschecklistbox

How can I change the Item Height in a checklistbox so the item text is not cut-off?

When I create a checklistbox on a form and populate the y's, g's, etc. get cut-off by the next item. I've found similar questions answered from years ago (How to change CheckedListBox item vertical space) and tried implementing their fixes but there's not enough details to work it out.

Right now, I go to add -> new item -> class and add a class to my solution. The class looks like this

using System.Windows.Forms;

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

And the object appears in my toolbox like this.

but once I drag and drop it to the form it gives me this enter image description here

If anyone can point out what I'm doing wrong it would be a great help. This has frustrated me to no end. Thanks!

Solution

  • Unfortunately Visual Studio 2017 (2019?) still doesn't play nicely with 64-bit controls in the Toolbox. This is primarily because VS is a 32-bit application.

    The normal solution is to build the project that contains your custom control(s) for the "Any CPU" platform. This might even mean creating a separate Class Library project to house them.

    The quick and easy solution (subjective), is to add your custom control(s) to your Form in code and avoid the designer.

    If changing ItemHeight is the only creative thing you want to do, I'll offer a workaround that uses the standard CheckedListBox control and reflection.

    In your Form constructor, after the line InitializeComponent();, do the following:

    var heightField = typeof(CheckedListBox).GetField(
    "scaledListItemBordersHeight", 
    BindingFlags.NonPublic | BindingFlags.Instance
);

var addedHeight = 10; // Some appropriate value, greater than the field's default of 2

heightField.SetValue(clb, addedHeight); // Where "clb" is your CheckedListBox

    This requires:

    using System.Reflection;

    This works because, internally, ItemHeight is a read-only property that returns Font.Height + scaledListItemBordersHeight.