C#修改下拉框选项的高度

重写ListBox.DrawItem事件处理，别忘记将ListBox.DrawMode 设置为OwnerDrawVariable，ListBox.ItemHeight值改大一点，字体也适当放大一号。

        private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
        {
            e.DrawBackground();

            e.DrawFocusRectangle();

            StringFormat strFmt = new System.Drawing.StringFormat();

            strFmt.Alignment = StringAlignment.Near; //文本水平居中

            strFmt.LineAlignment = StringAlignment.Center; //文本垂直居中

            e.Graphics.DrawString(listBox1.Items[e.Index].ToString(), e.Font, new SolidBrush(e.ForeColor), e.Bounds, strFmt);
        }