前不久,有位朋友发帖,寻求颜色选择的COMBOBOX 的制作方法,经过试验,整理了出来,仅供参考。 (注:如有引用,请注明出处和作者) --闵峰(2005/08/06东莞) Private Sub filllistboxwithcolors() Me.ComboBox1.DrawMode = DrawMode.OwnerDrawFixed Me.ComboBox1.DropDownStyle = ComboBoxStyle.DropDownList Me.ComboBox1.ItemHeight = 15 ''''避免闪烁beginupdate Me.ComboBox1.BeginUpdate() ComboBox1.Items.Clear() Dim pi As Reflection.PropertyInfo For Each pi In GetType(Color).GetProperties(Reflection.BindingFlags.Public Or Reflection.BindingFlags.Static) Me.ComboBox1.Items.Add(pi.Name) Next ComboBox1.EndUpdate() End Sub Private Sub ComboBox1_DrawItem(ByVal sender As Object, ByVal e As System.Windows.Forms.DrawItemEventArgs) Handles ComboBox1.DrawItem If e.Index < 0 Then Exit Sub Dim rect As Rectangle = e.Bounds ''''每一项的边框 ''''绘制项如果被选中则显示高亮显示背景,否则用白色 If e.State And DrawItemState.Selected Then e.Graphics.FillRectangle(SystemBrushes.Highlight, rect) Else e.Graphics.FillRectangle(SystemBrushes.Window, rect) End If Dim colorname As String = ComboBox1.Items(e.Index) Dim b As New SolidBrush(Color.FromName(colorname)) ''''缩小选定项区域() rect.Inflate(-16, -2) ''''填充颜色(文字对应的颜色) e.Graphics.FillRectangle(b, rect) ''''绘制边框() e.Graphics.DrawRectangle(Pens.Black, rect) Dim b2 As Brush ''''确定显示的文字的颜色() If CInt(b.Color.R) + CInt(b.Color.G) + CInt(b.Color.B) > 128 * 3 Then b2 = Brushes.Black Else b2 = Brushes.White End If e.Graphics.DrawString(colorname, Me.ComboBox1.Font, b2, rect.X, rect.Y) End Sub Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load filllistboxwithcolors() End Sub
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