关于在winform中listbox里面显示图片的问题.
在listbox中显示控件,并且是根据图像的大小来定义item的高度.在实际的开发中发现item的itemheight是受限制的.解决的办法就只有重绘.
主要的是两个事件MeasureItem,DrawItem.以及listbox 的属性DrawMode = System.Windows.Forms.DrawMode.OwnerDrawVariable.
private void listBox1_MeasureItem(object sender, MeasureItemEventArgs e)
{
//重新设定item的高度的关键代码.
if (e.Index >= 0 && e.Index < this.listBox1.Items.Count)
{
ImageHelp ih = (ImageHelp)this.listBox1.Items[e.Index];
e.ItemHeight= ih.img.Height;
}
}
private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
{
//绘制图片到item中.
Graphics g = e.Graphics;
// draw background, which indicates if object is selected
e.DrawBackground();
if (e.Index >= 0 && e.Index < this.listBox1.Items.Count)
{
// each item in the list IPainter
IPainter painter = new ColorPainter(Color.White);
ImageHelp ih = (ImageHelp)this.listBox1.Items[e.Index];
// get brush from painter
Brush brush = painter.PaintBrush;
// fill the item with painters brush
g.FillRectangle(brush, e.Bounds);
g.DrawLine(Pens.Black, e.Bounds.X, e.Bounds.Bottom - 1, e.Bounds.Right, e.Bounds.Bottom - 1);
// draw box with painter name
string name = ih.name;
int width = (int)g.MeasureString(name, this.listBox1.Font).Width;
g.FillRectangle((e.State & DrawItemState.Selected) == DrawItemState.Selected ? Brushes.Yellow : Brushes.White, 3, e.Bounds.Top, width + 3, this.listBox1.Font.Height);
// g.DrawRectangle(Pens.Black, 3, e.Bounds.Top + 3, width + 3, this.listBox1.Font.Height );
g.DrawString(name, Font, Brushes.Black, 5, e.Bounds.Top);
Rectangle photoRct = new Rectangle(
e.Bounds.X+40,
e.Bounds.Y,
ih.img.Width,
ih.img.Height);
e.Graphics.DrawImage(ih.img, photoRct);
brush.Dispose();
}
}
程序运行图片.
