挖一下 SuspendLayout, ResumeLayout 的原理 最近看到一些 winform 控件的写法里面,在设定 DockStyle 或者增减子控件的时候,往往先调用 SuspendLayout 方法,操作完毕之后调用一下 ResumeLayout. 不太明白其中的道理。所以用 Reflector 来看一下。代码在 System.Windows.Forms.Control 中。做一个简单的记录如下: public void SuspendLayout(){ this.layoutSuspendCount = (byte) (this.layoutSuspendCount + 1);}public void ResumeLayout(){ this.ResumeLayout(true);} public void ResumeLayout(bool performLayout){ if (this.layoutSuspendCount > 0) { this.layoutSuspendCount = (byte) (this.layoutSuspendCount - 1); if (((this.layoutSuspendCount == 0) && ((this.state & 0x200) != 0)) && performLayout) { this.PerformLayout(); } } if (!performLayout) { Control.ControlCollection collection1 = (Control.ControlCollection) this.Properties.GetObject(Control.PropControlsCollection); if (collection1 != null) { for (int num1 = 0; num1 < collection1.Count; num1++) { Control.LayoutManager.UpdateAnchorInfo(collection1[num1]); } } }} [EditorBrowsable(EditorBrowsableState.Advanced)]public void PerformLayout(){ this.PerformLayout(null, null);} [EditorBrowsable(EditorBrowsableState.Advanced)]public void PerformLayout(Control affectedControl, string affectedProperty){ if (!this.GetAnyDisposingInHierarchy()) { if (this.layoutSuspendCount > 0) { this.state |= 0x200; } else { this.layoutSuspendCount = 1; try { this.OnLayout(new LayoutEventArgs(affectedControl, affectedProperty)); } finally { this.state &= -513; this.layoutSuspendCount = 0; } } }}