How to disable the line under tool strip in winform c#?
问题 this line ? 回答1: It's a bug in the "system" renderer, details in this bug report. Microsoft's response gives a very easy workaround: 1) Create a subclass of ToolStripSystemRenderer , overriding OnRenderToolStripBorder and making it a no-op: public class MySR : ToolStripSystemRenderer { public MySR() { } protected override void OnRenderToolStripBorder(ToolStripRenderEventArgs e) { //base.OnRenderToolStripBorder(e); } } 2) Use that renderer for your toolstrip: toolStrip3.Renderer = new MySR();