Question

无法将类型“System.Data.SqlClient.SqlCommand”隐式转换为“System.Data.SqlClient.SqlConnection

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;

namespace ADO汇总
{
  class Program
  {
  static void Main(string[] args)
  {
  string dataDir = AppDomain.CurrentDomain.BaseDirectory;
  if (dataDir.EndsWith(@"\bin\Debug\")
  || dataDir.EndsWith(@"\bin\Release\"))
  {
  dataDir = System.IO.Directory.GetParent(dataDir).Parent.Parent.FullName;
  AppDomain.CurrentDomain.SetData("DataDirectory", dataDir);
  }

  using (SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\MyData1.mdf;Integrated Security=True;User Instance=True"))
  {
  conn.Open();
  using (SqlConnection cmd = conn.CreateCommand())

  {
  //我还没有开始写他就报这个错了，另外我创建的cmd. 里面有值，但没有Command。求助。。。
  }
   
  }

  Console.WriteLine("okay!!!!!!!!!");
  Console.ReadKey();
  }
  }
}

法将类型“System.Data.SqlClient.SqlCommand”隐式转换为“System.Data.SqlClient.SqlConnection

Answer 1

using (SqlConnection cmd = conn.CreateCommand())这句错了，
应该是using (SqlCommand cmd = conn.CreateCommand())