C＃存储过程的参数 [英] C# stored procedure with parameters

问题描述

我收到了我的应用程序中的错误，我无法弄清楚如何解决它。下面是代码：

I am receiving an error in my application and i can not figure out how to resolve it. Here is the code:

SqlConnection myConnection = new SqlConnection(ConfigurationManager.ConnectionStrings["DBConnection"].ConnectionString);
myConnection.Open();

SqlCommand cmd = new SqlCommand("SELECT ServerIP FROM Servers", myConnection);

SqlDataReader rdr = cmd.ExecuteReader();

if (rdr.HasRows)
{
   while (rdr.Read())
   {
      string serverIP = rdr["ServerIP"].ToString();
      ScheduledTasks st = new ScheduledTasks(@"\\" + serverIP);
      string[] taskNames = st.GetTaskNames();

      foreach (string name in taskNames)
      {
         Task t = st.OpenTask(name);
         var status = t.Status;
         var recentRun = t.MostRecentRunTime;
         var nextRun = t.NextRunTime;
         var appName = t.ApplicationName;

         SqlConnection myConnection2 = new SqlConnection(ConfigurationManager.ConnectionStrings["DBConnection"].ConnectionString);
         SqlCommand myCommand2 = new SqlCommand("sp_AddScheduledTasks", myConnection2);

         try
         {
            myConnection2.Open();
            myCommand2.CommandType = CommandType.StoredProcedure;
            myCommand2.Parameters.Add("@ID", SqlDbType.Int);
            myCommand2.Parameters["@ID"].Direction = ParameterDirection.Output;
            myCommand2.Parameters.Add("@ServerIP", SqlDbType.NVarChar, 20).Value = serverIP;
            myCommand2.Parameters.Add("@TaskName", SqlDbType.NVarChar, 50).Value = t;
            myCommand2.Parameters.Add("@MostRecentRun", SqlDbType.DateTime).Value = recentRun;
            myCommand2.Parameters.Add("@NextRunTime", SqlDbType.DateTime).Value = nextRun;
            myCommand2.Parameters.Add("@AppName", SqlDbType.NVarChar, 50).Value = appName;
            myCommand2.Parameters.Add("@Status", SqlDbType.NVarChar, 50).Value = status;

            int rows = myCommand2.ExecuteNonQuery();
         }
         finally
         {
            myConnection2.Close();
         }

我收到的错误是与的ExecuteNonQuery 。它说

InvalidCastException的从任务到
A字符串未能
转换参数值。

InvalidCastException Failed to convert parameter value from a Task to a String.

我认为它有一些东西需要做，我把试（if语句中），但我不知道。任何帮助将非常感激。

I thought it had something to do with where I put the try (inside the if statement) but I am not sure. Any help would be much appreciated.

谢谢，

太

推荐答案

我的猜测是，在

   myCommand2.Parameters.Add("@TaskName", SqlDbType.NVarChar, 50).Value = t;

t不是一个字符串？

t is not a string?

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