想在vs2005的c++环境，利用zedGraph控件，在窗体Form1中实现曲线显示，程序如下。调试时语法没错，但就是不能显示图形，不知是怎么回事，还请高手指点迷津。谢谢了先！

private: System::Void Form1_Load(System::Object^  sender, System::EventArgs^  e) {

    GraphPane myPane = zedGraphControl1->GraphPane;
    myPane.CurveList->Clear();

     // 设置初始数据
    double x, y1, y2;
    PointPairList^ list1 = gcnew PointPairList();
    PointPairList^ list2 = gcnew PointPairList();
    for ( int i=0; i<60; i++ )
      {
          x = (double) i + 5;
          y1 = 1.5 + Math::Sin( (double) i * 0.2 );
          y2 = 3.0 * ( 1.5 + Math::Sin( (double) i * 0.2 ) );
          list1->Add( x, y1 );
          list2->Add( x, y2 );
       }

    // 创建红色的菱形曲线
    // 标记, 图中的 "Porsche"
    LineItem myCurve1 = myPane.AddCurve("Porsche",list1, Color::Red, SymbolType::Diamond );

    // 创建蓝色的圆形曲线
    // 标记, 图中的 "Piper"   
    LineItem myCurve2 = myPane.AddCurve("Piper",list2, Color::Blue, SymbolType::Circle );

    // 在数据变化时绘制图形
    myPane.AxisChange(this->CreateGraphics());
   
                  
    }
   
private: System::Void Form1_Paint(System::Object^  sender, System::Windows::Forms::PaintEventArgs^  e) {

            
             GraphPane myPane = zedGraphControl1->GraphPane;   
             myPane.Draw( e->Graphics );


         }