C＃Lumenworks Csvreader-在讀取包含空/空字段的csv文件時在消息框中顯示錯誤

Question

我有這段代碼來讀取一個csv文件並將這些字段存儲在'Records'類的objects_Records列表中。

private String text2,text3,text4,text5,text6; 
    private double text7,text8,text9; 
    private int text1; 
    private int count = 0; 
    private void button1_Click(object sender, EventArgs e) 
    { 
     openFileDialog1.Filter = "CSV files (*.csv)|*.csv"; // Show only .csv files among all the different files   
     DialogResult result = openFileDialog1.ShowDialog(); // Show the dialog. 
     if (result == DialogResult.OK) // Test result. 
     { 
      String file = openFileDialog1.FileName; 
      try 
      { 
       textBoxFilePath.Text = file; 
       using (CsvReader csv = new CsvReader(new StreamReader(file), true)) 
       { 
        int fieldCount = csv.FieldCount; 
        string[] headers = csv.GetFieldHeaders(); 
        while (csv.ReadNextRecord()) 
        { 
         count += 1; 
          for (int i = 0; i < fieldCount; i++) 
          {       
           switch (headers[i].ToLower()) 
           { 
            case "plot": 
             text1 = int.Parse(csv[i]); 
             break; 
            case "local name": 
             text2 = csv[i]; 
             break; 
            case "botanical name": 
             text3 = csv[i]; 
             break; 
            case "genera": 
             text4 = csv[i]; 
             break; 
            case "species": 
             text5 = csv[i]; 
             break; 
            case "family": 
             text6 = csv[i]; 
             break; 
            case "dbh": 
             text7 = Double.Parse(csv[i]); 
             break; 
            case "ba(sqm)": 
             text8 = Double.Parse(csv[i]); 
             break; 
            case "ba": 
             text8 = Double.Parse(csv[i]); 
             break; 
            case "height": 
             text9 = Double.Parse(csv[i]); 
             break; 
            default: 
             MessageBox.Show("Please check the column headers of the fields once!"); 
             continue; 
            } 
          } 
          object_Records.Add(new Records(text1, text2, text3, text4, text5, text6, text7, text8, text9)); 
         } 
        } 
        textBox1.Text = count.ToString(); 
      } 
      catch (IOException) 
      { 
      } 
     } 
    } 

我的代碼對於沒有'NULL/EMPTY'字段的csv文件運行良好。遇到包含「NULL」字段的csv文件時，它會引發異常。

A first chance exception of type 'System.FormatException' occurred in mscorlib.dll 

附加信息：輸入字符串格式不正確。

請幫助我解決可以處理該異常的異常處理機制。

Answer 1

正如意見建議，你嘗試過本作的switch聲明：

switch (headers[i].ToLower()) 
{ 
    case "plot": 
     int.TryParse(csv[i], out text1); 
     break; 
    case "local name": 
     text2 = csv[i]; 
     break; 
    case "botanical name": 
     text3 = csv[i]; 
     break; 
    case "genera": 
     text4 = csv[i]; 
     break; 
    case "species": 
     text5 = csv[i]; 
     break; 
    case "family": 
     text6 = csv[i]; 
     break; 
    case "dbh": 
     Double.TryParse(csv[i], out text7); 
     break; 
    case "ba(sqm)": 
     Double.TryParse(csv[i], text8); 
     break; 
    case "ba": 
     Double.TryParse(csv[i], out text8); 
     break; 
    case "height": 
     Double.TryParse(csv[i], out text9); 
     break; 
    default: 
     MessageBox.Show("Please check the column headers of the fields once!"); 
     continue; 
} 

如果你嘗試過了，它不工作，你可以鑽到例外，看看究竟哪裏是被拋出？