Question

这是我的数据表：

DataTable CSVFile = new DataTable();
CSVFile.Columns.Add("Occurrence_Date", typeof(DateTime));
CSVFile.Columns.Add("Preanalytical_Before_Testing", typeof(string));
CSVFile.Columns.Add("Cup_Type", typeof(string));
CSVFile.Columns.Add("Analytical_Testing_Phase", typeof(string));
CSVFile.Columns.Add("Area", typeof(string));
CSVFile.Columns.Add("Postanalytical_After_Testing", typeof(string));
CSVFile.Columns.Add("Other", typeof(string));
CSVFile.Columns.Add("Practice_Code", typeof(string));
CSVFile.Columns.Add("Comments", typeof(string));

我正在尝试添加一个新行：

DataRow newRow = CSVFile.NewRow();
newRow["Occurrence_Date"] =  Convert.ToDateTime(splitcsvlines[GetColumnsNames.Occurrence_Date]);
newRow["Preanalytical_Before_Testing"] = splitcsvlines[GetColumnsNames.Preanalytical_Before_Testing];
newRow["Cup_Type"] = splitcsvlines[GetColumnsNames.Cup_Type];
newRow["Analytical_Testing_Phase"] = splitcsvlines[GetColumnsNames.Analytical_Testing_Phase];
newRow["Area"] = splitcsvlines[GetColumnsNames.Area];
newRow["Postanalytical_After_Testing"] = splitcsvlines[GetColumnsNames.Postanalytical_After_Testing];
newRow["Other"] = splitcsvlines[GetColumnsNames.Other];
newRow["Practice_Code"] = splitcsvlines[GetColumnsNames.Practice_Code];
newRow["Comments"] = splitcsvlines[GetColumnsNames.Comments];
CSVFile.Rows.Add(newRow);

但是我收到错误

'BulkUploadToLOMDatabase.GetColumnsNames'的类型初始值设定项引发异常。

我尝试过newRow["Cup_Type"] = "something"或newRow[2] = "something"但仍然遇到同样的错误

以下是该课程的内容：

class GetColumnsNames
{

  public static int Occurrence_Date = Convert.ToInt16(ConfigurationSettings.AppSettings["Occurrence_Date"].ToString());
  public static int Preanalytical_Before_Testing = Convert.ToInt16(ConfigurationSettings.AppSettings["1_0_Preanalytical_Before_Testing"].ToString());
  public static int Cup_Type = Convert.ToInt16(ConfigurationSettings.AppSettings["Cup_Type"].ToString());
  public static int Analytical_Testing_Phase = Convert.ToInt16(ConfigurationSettings.AppSettings["Analytical_Testing_Phase"].ToString());
  public static int Area = Convert.ToInt16(ConfigurationSettings.AppSettings["Area"].ToString());
  public static int Postanalytical_After_Testing = Convert.ToInt16(ConfigurationSettings.AppSettings["Postanalytical_After_Testing"].ToString());
  public static int Other = Convert.ToInt16(ConfigurationSettings.AppSettings["Other"].ToString());
  public static int Practice_Code = Convert.ToInt16(ConfigurationSettings.AppSettings["Practice_Code"].ToString());
  public static int Comments = Convert.ToInt16(ConfigurationSettings.AppSettings["Comments"].ToString());
}

我做错了什么？我班上有什么问题？

Answer 1

The type initializer for BulkUploadToLOMDatabase.GetColumnsNames' threw an exception.

这意味着CLR尝试创建您的类型但失败了。由于您有许多依赖于KeyNotFound FormatExecption NullException失败的调用的静态变量，您应该将此类转换为singleton。

这样您就可以正确捕获ConfigurationSettings.AppSettings

的任何问题

另外，您可能需要考虑使用system.configuration.configurationmanager。这是除非你在1.1。 ConfigurationSettings.AppSettings在2.0中已经过时了

Answer 2

确保ConfigurationSettings.AppSettings具有您要求的那些整数值。看起来这就是抛出错误。

您的数据表和数据路码很好。

Answer 3

我认为问题出现是因为这行代码：

public static int Occurrence_Date = Convert.ToInt16(ConfigurationSettings.AppSettings["Occurrence_Date"].ToString());

int32值无法转换为DateTime值：

newRow["Occurrence_Date"] =  Convert.ToDateTime(splitcsvlines[GetColumnsNames.Occurrence_Date]);

正如@LarsTech所说，您的dataTable相关代码是正确的。最危险的是我上面发布的代码。请在一个简单的控制台中实现它（ConfigurationSettings.AppSettings [“Occurrence_Date”]。ToString（））特定值转换为int15然后转换为DateTime。你有什么结果？

Answer 4

正如其他人所提到的，构建/加载表格很好......这里是快速测试，使用序号位置与列名称来加载10个随机值。您在评论中说调试显示正确的值，如果是，那么一切都应该正常工作。只需“确保”您获得每个列值的预期数据类型。

        DataTable CSVFile = new DataTable();
        CSVFile.Columns.Add("Occurrence_Date", typeof(DateTime));
        CSVFile.Columns.Add("Preanalytical_Before_Testing", typeof(string));
        CSVFile.Columns.Add("Cup_Type", typeof(string));
        CSVFile.Columns.Add("Analytical_Testing_Phase", typeof(string));
        CSVFile.Columns.Add("Area", typeof(string));
        CSVFile.Columns.Add("Postanalytical_After_Testing", typeof(string));
        CSVFile.Columns.Add("Other", typeof(string));
        CSVFile.Columns.Add("Practice_Code", typeof(string));
        CSVFile.Columns.Add("Comments", typeof(string));

        for (int i = 0; i < 10; i++)
        {
            DataRow row = CSVFile.NewRow();
            row[0] = DateTime.Now.AddDays(i);
            row[1] = "Field 2";
            row[2] = "Field 3";
            row[3] = "Field 4";
            row[4] = "Field 5";
            row[5] = "Field 6";
            row[6] = "Field 7";
            row[7] = "Field 8";
            row[8] = "Field 9";

            CSVFile.Rows.Add(row);
        }

无法在DataTable中添加新行

4 个答案: