后来，再次作一个完全独立的测试项目，发现 Splitter 的使用有个算是 bug 的问题，如果你首先放两个 Panel ，然后再放一个 Splitter 。（注意这时候的次序）就会产生我上面出现的问题。这时候代码中的 InitializeComponent 函数部分代码如下：
代码如下:
private void InitializeComponent()
{
//
// ... 其他代码
//
this.panel1 = new System.Windows.Forms.Panel();
this.panel2 = new System.Windows.Forms.Panel();
this.splitter1 = new System.Windows.Forms.Splitter();
this.panel2.SuspendLayout();
this.SuspendLayout();
//
// ... 其他代码
//
//
// panel1
//
this.panel1.Dock = System.Windows.Forms.DockStyle.Left;
this.panel1.Location = new System.Drawing.Point(0, 42);
this.panel1.Name = "panel1";
this.panel1.Size = new System.Drawing.Size(120, 209);
this.panel1.TabIndex = 6;
this.panel1.Resize += new System.EventHandler(this.panel2_Resize);
this.panel1.Paint += new System.Windows.Forms.PaintEventHandler(this.panel2_Paint);
//
// panel2
//
this.panel2.Controls.Add(this.splitter1);
this.panel2.Dock = System.Windows.Forms.DockStyle.Fill;
this.panel2.Location = new System.Drawing.Point(120, 42);
this.panel2.Name = "panel2";
this.panel2.Size = new System.Drawing.Size(328, 209);
this.panel2.TabIndex = 7;
this.panel2.Resize += new System.EventHandler(this.panel2_Resize);
this.panel2.Paint += new System.Windows.Forms.PaintEventHandler(this.panel2_Paint);
//
// splitter1
//
this.splitter1.BackColor = System.Drawing.SystemColors.Desktop;
this.splitter1.Location = new System.Drawing.Point(0, 0);
this.splitter1.Name = "splitter1";
this.splitter1.Size = new System.Drawing.Size(3, 209);
this.splitter1.TabIndex = 0;
this.splitter1.TabStop = false;
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(448, 273);
this.Controls.Add(this.panel2);
this.Controls.Add(this.panel1);
this.Controls.Add(this.toolBar1);
this.Controls.Add(this.statusBar1);
this.Name = "Form1";
this.Text = "站点下载工具 2003年9月21日";
this.panel2.ResumeLayout(false);
this.ResumeLayout(false);
}
注意：这时候的代码中的顺序。这时候，程序的执行是有问题的。分隔条会不起作用。
但是如果你把这三个控件放入顺序修改为下面的顺序就没有问题了。
1、放入一个 Panel 比如：panel1 然后设置他的 Dock 属性为：Left;
2、放入一个 Splitter 比如：splitter1 设置它的背景颜色为一个特殊的颜色，便于看执行效果；
3、放入一个 Panel 比如：panel2 然后设置他的 Dock 属性为：Fill;
4、编译执行程序，这时候就没有问题了。
这时候正确的代码应该是：（ InitializeComponent 函数部分）
代码如下:
private void InitializeComponent()
{
//
// ... 其他代码
//
this.panel1 = new System.Windows.Forms.Panel();
this.panel2 = new System.Windows.Forms.Panel();
this.splitter1 = new System.Windows.Forms.Splitter();
this.panel2.SuspendLayout();
this.SuspendLayout();
//
// ... 其他代码
//
//
// panel1
//
this.panel1.Dock = System.Windows.Forms.DockStyle.Left;
this.panel1.Location = new System.Drawing.Point(0, 42);
this.panel1.Name = "panel1";
this.panel1.Size = new System.Drawing.Size(200, 209);
this.panel1.TabIndex = 6;
//
// panel2
//
this.panel2.Controls.Add(this.splitter1);
this.panel2.Dock = System.Windows.Forms.DockStyle.Fill;
this.panel2.Location = new System.Drawing.Point(200, 42);
this.panel2.Name = "panel2";
this.panel2.Size = new System.Drawing.Size(248, 209);
this.panel2.TabIndex = 7;
//
// splitter1
//
this.splitter1.BackColor = System.Drawing.SystemColors.Desktop;
this.splitter1.Location = new System.Drawing.Point(0, 0);
this.splitter1.Name = "splitter1";
this.splitter1.Size = new System.Drawing.Size(3, 209);
this.splitter1.TabIndex = 0;
this.splitter1.TabStop = false;
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(448, 273);
this.Controls.Add(this.panel2);
this.Controls.Add(this.panel1);
this.Controls.Add(this.toolBar1);
this.Controls.Add(this.statusBar1);
this.Menu = this.mainMenu1;
this.Name = "Form1";
this.Text = "站点下载工具 2003年9月21日";
this.Load += new System.EventHandler(this.Form1_Load);
this.panel2.ResumeLayout(false);
this.ResumeLayout(false);
}