呼叫信息與鼠標點擊事件參數的方法

Question

我怎麼能叫與系統參數的方法在鼠標點擊事件：

public void DrawStringRectangleF(PaintEventArgs e) 
{ 

    // Create string to draw. 
    String drawString = "Sample Text"; 

    // Create font and brush. 
    Font drawFont = new Font("Arial", 16); 
    SolidBrush drawBrush = new SolidBrush(Color.Black); 

    // Create rectangle for drawing. 
    float x = 150.0F; 
    float y = 150.0F; 
    float width = 200.0F; 
    float height = 50.0F; 
    RectangleF drawRect = new RectangleF(x, y, width, height); 

    // Draw rectangle to screen. 
    Pen blackPen = new Pen(Color.Black); 
    e.Graphics.DrawRectangle(blackPen, x, y, width, height); 

    // Draw string to screen. 
    e.Graphics.DrawString(drawString, drawFont, drawBrush, drawRect); 
} 

我想打電話給在此情況下，本方法：

private void button1_Click(object sender, EventArgs e) 
     { 
      // calling DrawStringRectangleF(PaintEventArgs e) here 
     } 

如果參數只是在調用這些方法時提及這些值，則很容易調用該方法，但在這種情況下如何調用它？！

Answer 1

爲了滿足你可以封裝你想用來繪製矩形的PaintEventArgs類的實例中這樣

using (var controlGraphics = CreateGraphics()) 
{ 
    var paintEventArgs = new PaintEventArgs(controlGraphics, ClientRectangle); 
    DrawStringRectangleF(paintEventArgs); 
} 

的Control.CreateGraphics方法會產生Graphics的Graphics例如現有的方法簽名您可以使用它來繪製底層控件（或表單）上的實例。

要明白，每當控件失效時，用該Graphics對象繪製的所有內容都將被擦除，因此您必須連續重新繪製圖形。

您可能會考慮改變方法簽名，使其接受的Graphics，而不是它的實例應該爲一個清晰的解決方案。

Answer 2

下面是使用畫圖（）事件和自定義類的列表來存儲應該怎麼得出的信息的一個例子：

public partial class Form1 : Form 
{ 

    public class TextData 
    { 
     public string Text; 
     public string FontName; 
     public int FontSize; 
     public RectangleF TextRectF; 
     public Color TextColor; 
    } 

    private List<TextData> Texts = new List<TextData>(); 

    public Form1() 
    { 
     InitializeComponent(); 
     this.Paint += new PaintEventHandler(Form1_Paint); 

     TextData td = new TextData(); 
     td.Text = "Example"; 
     td.FontName = "Courier"; 
     td.FontSize = 24; 
     td.TextRectF = new RectangleF(50.0F, 50.0F, 175.0F, 75.0F); 
     td.TextColor = Color.Red; 
     Texts.Add(td); 
    } 

    void Form1_Paint(object sender, PaintEventArgs e) 
    { 
     foreach (TextData td in Texts) 
     { 
      using (Pen drawPen = new Pen(td.TextColor)) 
      { 
       e.Graphics.DrawRectangle(drawPen, Rectangle.Round(td.TextRectF)); 
      } 
      using (Font drawFont = new Font(td.FontName, td.FontSize)) 
      { 
       using (SolidBrush drawBrush = new SolidBrush(td.TextColor)) 
       { 
        e.Graphics.DrawString(td.Text, drawFont, drawBrush, td.TextRectF);    
       } 
      } 
     } 
    } 

    private void button1_Click(object sender, EventArgs e) 
    { 
     TextData td = new TextData(); 
     td.Text = "Sample Text"; 
     td.FontName = "Arial"; 
     td.FontSize = 16; 
     td.TextRectF = new RectangleF(150.0F, 150.0F, 200.0F, 50.0F); 
     td.TextColor = Color.Black; 
     Texts.Add(td); 
     this.Refresh(); 
    } 

}