C# MySql 0x80004005) : an error in SQL syntax;

Question

我的代码偶尔会出错(windows 服务)。我用了断点，但是什么也没有。谁能帮帮我

 private void SetGPSIsLogOut(int shopId,int status)
    {
        MySqlConnection conn = ConnectDataBase();
        strcmd.Clear();
        strcmd.AppendLine("update multi_shop_gps_location_log set gps_is_logout="+status+" where shop_id=" + shopId + " ");
        MySqlCommand myCommand = new MySqlCommand(strcmd.ToString());
        myCommand.Connection = conn;
        try
        {
            conn.Open();
            myCommand.ExecuteNonQuery();
            conn.Close();
        }
        catch (MySqlException e)
        {
            UpdateServicestatus(-1);
            WriteLog("SetGPSIsLogOut 更新失败" + e);
        }
    }

异常(exception):

MySql.Data.MySqlClient.MySqlException (0x80004005): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'update multi_shop_gps_location_log set gps_is_logout=0 where shop_id=513' at line 2 在 MySql.Data.MySqlClient.MySqlStream.ReadPacket() 在 MySql.Data.MySqlClient.NativeDriver.GetResult(Int32& affectedRow, Int64& insertedId) 在 MySql.Data.MySqlClient.Driver.GetResult(Int32 statementId, Int32& affectedRows, Int64& insertedId) 在 MySql.Data.MySqlClient.Driver.NextResult(Int32 statementId, Boolean force) 在 MySql.Data.MySqlClient.MySqlDataReader.NextResult() 在 MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior) 在 MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery() 在 ys_service.Service1.SetGPSIsLogOut(Int32 shopId, Int32 status) 位置 E:\service\service\Service1.cs:行号 645

帮助

请

Answer 1

错误是由于您没有在连接的查询字符串上使用引号引起的。

但是正确的方法是使用参数而不是字符串连接:

...
string query ="update multi_shop_gps_location_log set gps_is_logout=@status where shop_id=@shopId";
MySqlCommand myCommand = new MySqlCommand(query);
myCommand.Parameters.Add("@status",status);
myCommand.Parameters.Add("@shopId ",shopId );
...