c# - 删除字符串变量中存储的值的最后两个字符

Question

我正在 VS2010 C# 中开发一个应用程序，用于从 SQLServer 获取单行数据并将其插入 MySQL。

我已获取数据并将其存储在特定的字符串变量中。获取代码如下。

SqlCommand cmd = new SqlCommand("SELECT TOP (1) s_name, s_city, s_address, s_added_date, s_added_by FROM tblAQI ORDER BY s_added_date DESC", SSCon);
        SqlDataReader dr = cmd.ExecuteReader();
        while (dr.Read())
        {
            s_name = (dr["s_name"].ToString());
            s_city = (dr["s_city"].ToString());
            s_address = (dr["s_address"].ToString());
            s_added_date = (dr["s_added_date"].ToString());
            s_added_by = (dr["s_added_by"].ToString());
        }

全部以字符串格式存储值。问题在于 s_added_date 这个变量包含日期时间值，例如 11/15/2013 12:01:00 AM 无法插入 MySQL，我认为是因为 AM。

我的插入代码如下。

            mcmd.CommandText = "INSERT INTO tblaqi(s_name,s_city,s_address,s_added_date,s_added_by) VALUES(@s_name,@s_city,@s_address,s_added_date,s_added_by)";
        mcmd.Parameters.AddWithValue("@s_name", s_name);
        mcmd.Parameters.AddWithValue("@s_city", s_city);
        mcmd.Parameters.AddWithValue("@s_address", s_address);
        mcmd.Parameters.AddWithValue("@s_added_by", s_added_by);
        mcmd.Parameters.AddWithValue("@s_added_date", s_added_date);

        int count = mcmd.ExecuteNonQuery();
        if (count != 0)
        {
            MessageBox.Show("Success..!!");
        }
        else
            MessageBox.Show("Need to work");

我的问题是这会出现什么问题。

提前致谢。

Answer 1

解决方案 1:您的查询无效:您在 insert into 语句中缺少参数的 @ 符号，如下所示

mcmd.CommandText = "INSERT INTO tblaqi(s_name,s_city,s_address,s_added_date,s_added_by) VALUES(@s_name,@s_city,@s_address,s_added_date,s_added_by)";
                                                                                                                          ^^^          ^^^

应该是这样的:

 mcmd.CommandText = "INSERT INTO tblaqi(s_name,s_city,s_address,s_added_date,s_added_by) VALUES(@s_name,@s_city,@s_address,@s_added_date,@s_added_by)";

解决方案 2:

s_added_date=s_added_date.Substring(0, s_added_date.Length - 3);//stores only 11/15/2013 12:01:00