Question

作为我尝试开发的应用程序的一部分，是根据服务类型更新记录。因此，Status属性的等级从1到8（进行中= 3和完成= 5）。我创建了我的代码，但它似乎无法正常工作，因为我尝试传递值并测试更新当前服务类型如下：

如果进展，则更新为4
如果已完成，则更新6

class Program
{
    static void Main(string[] args)
    {
        int Bend = 4;
        int Complete = 6;

        List<int> Status = new List<int>();

        foreach (int i in Status)
        {
            if (i == 3)
            {
                SqlConnection con = new SqlConnection(@"Data Source=
              (localdb)\Projects;Initial Catalog=FLS_DB;Integrated 
               Security=True;Connect Timeout=30;Encrypt=False;");
                con.Open();
                SqlCommand cmd = new SqlCommand("Update Calls set 
                Service =@Service", con);
                cmd.CommandType = CommandType.Text;
                cmd.Parameters.AddWithValue("@Service", Bend);
                con.Open();
                int rowsAffected = cmd.ExecuteNonQuery();
                con.Close();
            }
            else if (i == 5)
            {
                SqlConnection con = new SqlConnection(@"Data Source= 
               (localdb)\Projects;Initial Catalog=FLS_DB;Integrated 
               Security=True;
               Connect Timeout=30;Encrypt=False;");
                con.Open();
                SqlCommand cmd = new SqlCommand("Update Calls set 
                   Service =@Service", con);
                cmd.CommandType = CommandType.Text;
                cmd.Parameters.AddWithValue("@Service", Complete);
                con.Open();
                int rowsAffected = cmd.ExecuteNonQuery();
                con.Close();
            }
        }
    }
}

非常感谢任何帮助！

Answer 1

您的代码缺少WHERE语句，只更新符合条件i == 3或i == 5的记录，因此您似乎不需要循环。

您只需将服务列设置为服务列中包含值3或5的所有记录的新值Bend和Complete

using(SqlConnection con = new SqlConnection(....))
using(SqlCommand cmd = con.CreateCommand())
{
   con.Open();
   // Sets to 4 all records with 3
   cmd.CommandText = "Update Calls set Service=@Service WHERE Service=3" 
   cmd.Parameters.AddWithValue("@Service", Bend);
   int rowsUpdatedToBend = cmd.ExecuteNonQuery();

   // No need to recreate the command, just change the commandtext and
   // the value of the parameter @service
   cmd.CommandText = "Update Calls set Service=@Service WHERE Service=5" 
   cmd.Parameters["@Service"].Value = Complete
   rowsUpdatedToComplete = cmd.ExecuteNonQuery();

   MessageBox.Show("You have changed " + rowsUpdatedToBend + " rows to Bend state\r\n" + 
                   "You have changed " + rowsUpdatedToComplete + " rows to Complete state");
}

Answer 2

您的连接字符串是否正确？
按条件
设置断点并检查程序的运行位置

假设第一点是正确的;你可以尝试这样的事情（代码编辑）：

string commandText = "UPDATE Calls SET Service=Service + 1 WHERE Service = 3 OR Service = 5;";
string connectionString = @"Data Source=
          (localdb)\Projects;Initial Catalog=FLS_DB;Integrated 
           Security=True;Connect Timeout=30;Encrypt=False;";

    using (SqlConnection connection = new SqlConnection(connectionString))
    {            
        SqlCommand command = new SqlCommand(commandText, connection);            

        try
        {
            connection.Open();
            int rowsAffected = command.ExecuteNonQuery();
            Console.WriteLine("RowsAffected: {0}", rowsAffected);
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
        }
    }

更新数据库字段

2 个答案: