C#中 可以用Pen创建新画笔，并设定其颜色，但怎样使画笔颜色随即产生呢？？
例如要产生10条直线，要求10条直线的颜色随即产生，怎么办？/
急盼答复！！！！先行谢过！！！

这是我以前做的一个小程序你可以看一下


using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace 绘图
{
/// <summary>
/// Form1 的摘要说明。
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Panel panel1;
private System.Windows.Forms.Button button1;
/// <summary>
/// 必需的设计器变量。
/// </summary>
private System.ComponentModel.Container components = null;

public Form1()
{
//
// Windows 窗体设计器支持所必需的
//
InitializeComponent();

//
// TODO: 在 InitializeComponent 调用后添加任何构造函数代码
//
}

/// <summary>
/// 清理所有正在使用的资源。
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}

#region Windows 窗体设计器生成的代码
/// <summary>
/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
/// </summary>
private void InitializeComponent()
{
this.panel1 = new System.Windows.Forms.Panel();
this.button1 = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// panel1
//
this.panel1.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
this.panel1.Location = new System.Drawing.Point(0, 56);
this.panel1.Name = "panel1";
this.panel1.Size = new System.Drawing.Size(368, 248);
this.panel1.TabIndex = 0;
this.panel1.Paint += new System.Windows.Forms.PaintEventHandler(this.panel1_Paint);
//
// button1
//
this.button1.Location = new System.Drawing.Point(152, 16);
this.button1.Name = "button1";
this.button1.Size = new System.Drawing.Size(64, 23);
this.button1.TabIndex = 1;
this.button1.Text = "随机绘制";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
this.ClientSize = new System.Drawing.Size(368, 301);
this.Controls.Add(this.button1);
this.Controls.Add(this.panel1);
this.Name = "Form1";
this.Text = "Form1";
this.ResumeLayout(false);

}
#endregion

/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new Form1());
}

private void button1_Click(object sender, System.EventArgs e)
{
Random r=new Random();
int a=r.Next(0,3);
int b=r.Next(0,256);
int c=r.Next(0,256);
int d=r.Next(0,256);
if(a==0)
{
Graphics g=this.panel1.CreateGraphics();
g.DrawLine(new Pen(Color.Red,2.0f),0,0,b,c);
}
else if(a==1)
{
Graphics g=this.panel1.CreateGraphics();
g.DrawRectangle(new Pen(Color.Red,2.0f),0,0,b,c);
}
else if(a==2)
{
Graphics g=this.panel1.CreateGraphics();
g.DrawEllipse(new Pen(Color.FromArgb(b,c,d)),this.panel1.ClientRectangle);
}
}

private void panel1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
{
}
}
}