在颜色列表框插入项目 [英] ListBox insert items in color

问题描述

我使用 ListBox 插入文本，例如您在数据库中添加Michael ，删除Michael ，...

I use ListBox for inserting text like You add Michael in your database, You delete Michael, ...

 listBox1.Items.Insert(0,"You add " + name + " in your database\n");

它工作正常。如何设置颜色一次黑色（插入）和一次红色（删除）？我试过这个：

It works ok. How can i set color once black (for insert) and once red (for deletion)? I tried with this:

 public class MyListBoxItem
    {
        public MyListBoxItem(Color c, string m)
        {
            ItemColor = c;
            Message = m;
        }
        public Color ItemColor { get; set; }
        public string Message { get; set; }
    }

    private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
    {
        MyListBoxItem item = listBox1.Items[e.Index] as MyListBoxItem; // Get the current item and cast it to MyListBoxItem

        if (item != null)
        {
            e.Graphics.DrawString( // Draw the appropriate text in the ListBox
            item.Message, // The message linked to the item
            listBox1.Font, // Take the font from the listbox
            new SolidBrush(item.ItemColor), // Set the color 
            0, // X pixel coordinate
            e.Index * listBox1.ItemHeight // Y pixel coordinate.  Multiply the index by the ItemHeight defined in the listbox.
            );
        }
        else
        {
            // The item isn't a MyListBoxItem, do something about it
        }
    }

插入时：

 listBox1.Items.Insert(0, new MyListBoxItem(Color.Black, "You add " + name + " in your database\n"));
 listBox1.Items.Insert(0, new MyListBoxItem(Color.Red, "You delete " + name + "\n"));

此代码可以工作，但是当我插入多个项目时，scrol不能正常工作 - 文本不会出现。我做错了什么？

This code works, but when i insert multiple items, scrol doesn't work correctly - text does not appear. What am i doing wrong? Or is any other way to do this?

推荐答案

应该使用：

e.Bounds.Top

/ p>

instead of:

e.Index * listBox1.ItemHeight

此外，在绘制文本之前，我建议绘制背景，以便您可以看到选择哪个项目，如果列表支持选择，或者支持任何情况下的列表的所需项目背景颜色： p>

Also, before drawing the text, I recommend drawing the background so you can see which item is selected, if the list supports selection, or support the list's desired item background color in any case:

using (Brush fill = new SolidBrush(e.BackColor))
{
   e.Graphics.FillRectangle(fill, e.Bounds);
}

你应该正确处理你创建的Brush来绘制文本。

And you should properly dispose of the Brush that you're creating to draw the text.

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