關閉C上的窗體時發生錯誤＃

Question

我正在做一個簡單的測試程序，但是當我關閉窗體的關閉按鈕時（窗口右上方的正常按鈕，而不是按鈕）我自己）。

這是代碼，註釋只是爲了識別的人：

public partial class Preguntas : Form 
{ 
    int i = 0; 
    int j = 0; 

    int[] score = { 
     /*Vir*/ 0, 
     /*Eva*/ 0, 
     /*Pedro*/ 0 }; 

    string[] questions = new string[] { 
     /*Vir*/ "¿Qué prefiero ver?","2","3","4","5", 
     /*Eva*/ "a","2","3","4","5", 
     /*Pedro*/ "1","2","3","4","5", 
    }; 

    string[] opt1 = new string[] { 
     /*Vir*/ "Películas de serie B","2","3","4","5", 
     /*Eva*/ "1","2","3","4","5", 
     /*Pedro*/ "1","2","3","4","5", 
    }; 

    string[] opt2 = new string[] { 
     /*Vir*/ "Series","2","3","4","5", 
     /*Eva*/ "1","2","3","4","5", 
     /*Pedro*/ "1","2","3","4","5", 
    }; 

    string[] opt3 = new string[] { 
     /*Vir*/ "Películas romanticas","2","3","4","5", 
     /*Eva*/ "1","2","3","4","5", 
     /*Pedro*/ "1","2","3","4","5", 
    }; 

    string[] opt4 = new string[] { 
     /*Vir*/ "Películas de acción","2","3","4","5", 
     /*Eva*/ "1","2","3","4","5", 
     /*Pedro*/ "1","2","3","4","5", 
    }; 

    int[] correctAnswer = { 
     /*Vir*/ 1,1,1,1,1, 
     /*Eva*/ 1,1,1,1,1, 
     /*Pedro*/ 1,1,1,1,1 
    }; 


    public Preguntas() 
    { 
     InitializeComponent(); 
     RefreshTest(); 
    } 

    public void FinishTest() 
    { 
     i = 0; // I dont know why i have to put this but if not 
     j = 0; // a axception when close the program occurs. 
     Resultado f2 = new Resultado(score); 
     this.Hide(); 
     f2.ShowDialog(); 
     this.Close(); 
    } 

    public void RefreshTest() 
    { 
     if (i == 15) FinishTest(); 

     pictureBox1.Image = imageList1.Images[i]; 
     pictureBox2.Image = imageList2.Images[j]; 

     label1.Text = opt1[i]; 
     label2.Text = opt2[i]; 
     label3.Text = opt3[i]; 
     label4.Text = opt4[i]; 
     label5.Text = questions[i]; 

    } 

    public void Correction(int answer) 
    { 
     if(correctAnswer[i] == answer) 
     { 
      score[j] += 1; 
     } 

     if (++i % 5 == 0) j++; 

     RefreshTest(); 

    } 

    private void button1_Click(object sender, EventArgs e) 
    { 
     Correction(1); 
    } 

    private void button2_Click(object sender, EventArgs e) 
    { 
     Correction(2); 
    } 

    private void button3_Click(object sender, EventArgs e) 
    { 
     Correction(3); 
    } 

    private void button4_Click(object sender, EventArgs e) 
    { 
     Correction(4); 
    } 
} 

這是個例外：

類型「System.ArgumentOutOfRangeException」未處理的異常發生在System.Windows .Forms.dll

附加信息：InvalidArgument ='15'的值對'index'無效。

它發生在RefreshTest在這條線： pictureBox1.Image = imageList1.Images[i];

我想，當我點擊關閉butom程序完成RefreshTest因爲是在內存和最終運行它發現的一切，但我不知道如何避免它。

Answer 1

類型「System.ArgumentOutOfRangeException」 未處理的異常出現在System.Windows.Forms.dll中

這是因爲它無法找到元素，您正在尋找的圖像集。 在分配圖像之前，您必須確保您分配的圖像存在。 在此護理中，它被設置爲不在您的收藏中的前15名。

If(imageList1.Images.Count >= 15) 
{ 
    pictureBox1.Image = imageList1.Images[i]; 
} 

如果該方法，當你關閉你無論是在錯誤的時間關閉該程序的程序，或者你必須讓方法運行知道你正在關閉，因此它可以跳過代碼。你可以在關門活動中用一個標誌來做到這一點。

Answer 2

你可以只是包裝你的代碼的if-else語句，而不是你的唯一的IF語句如下：

public void RefreshTest() 
    { 
     if(i==15) 
     { 
      FinishTest(); 
     } 
     else 
     { 

      pictureBox1.Image = imageList1.Images[i]; 
      pictureBox2.Image = imageList2.Images[j]; 

      label1.Text = opt1[i]; 
      label2.Text = opt2[i]; 
      label3.Text = opt3[i]; 
      label4.Text = opt4[i]; 
      label5.Text = questions[i]; 

     } 
    }