c# - c#数据库选择然后插入。但值为0
问题描述
我正在尝试选择然后从表 1 到表 2 中插入一个日期时间。我已成功插入数据。但是,表 2 中显示的日期时间是 0000-00-00 00:00:00。我知道错误在哪里。有人请帮我解决这个问题。我正在为此苦苦挣扎。这是选择然后插入的正确方法吗?(从表 1 中选择,然后插入到表 2 中)
try
{
string myConnectionString;
myConnectionString= "server=localhost;uid=root;pwd=root;database=medicloud;SslMode=None;charset=utf8";
MySqlConnection connection = new MySqlConnection(myConnectionString);
MySqlCommand cmd = new MySqlCommand();
cmd.CommandType = CommandType.Text;
EncodingProvider ppp;
ppp = CodePagesEncodingProvider.Instance;
Encoding.RegisterProvider(ppp);
connection.Open();
string select = "Select time from assign where userId=@name";
cmd.Parameters.AddWithValue("@name", txtValue.Text);
cmd.CommandText = select;
cmd.Connection = connection;
MySqlDataReader selectAssign = cmd.ExecuteReader();
selectAssign.Read();
string assign = (selectAssign["time"].ToString());
selectAssign.Close();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "INSERT into bluetooth (userId,arm,armNumberDone,armNumber,comDate,assignDate,status) VALUES (@name, @stupid0, @stupid1, @stupid2, @stupid3, @stupid4, @stupid5)";
cmd.Parameters.AddWithValue("@stupid0", databaseLine);
cmd.Parameters.AddWithValue("@stupid1", counter);
cmd.Parameters.AddWithValue("@stupid2", databaseValue);
cmd.Parameters.AddWithValue("@stupid3", DateTime.Now);
cmd.Parameters.AddWithValue("@stupid4", assign);
cmd.Parameters.AddWithValue("@stupid5", complete);
cmd.Connection = connection;
cmd.ExecuteNonQuery();
connection.Close();
}
catch (MySqlException ex)
{
txtExercise.Text = ex.ToString();
}
解决方案
请试试这个
try
{
string myConnectionString;
myConnectionString = "server=localhost;uid=root;pwd=root;database=medicloud;SslMode=None;charset=utf8";
MySqlConnection connection = new
MySqlConnection(myConnectionString);
MySqlCommand cmd = new MySqlCommand();
cmd.CommandType = CommandType.Text;
EncodingProvider ppp;
ppp = CodePagesEncodingProvider.Instance;
Encoding.RegisterProvider(ppp);
connection.Open();
string select = "Select time from assign where userId=@name";
cmd.Parameters.AddWithValue("@name", txtValue.Text);
cmd.CommandText = select;
cmd.Connection = connection;
MySqlDataReader selectAssign = cmd.ExecuteReader();
selectAssign.Read();
string assign = (selectAssign["time"].ToString());
selectAssign.Close();
DateTime assignDate = DateTime.Now;
DateTime.TryParseExact(assign, out assignDate);
cmd.CommandType = CommandType.Text;
cmd.CommandText = "INSERT into bluetooth
(userId,arm,armNumberDone,armNumber,comDate,assignDate,status) VALUES (@name,
@stupid0, @stupid1, @stupid2, @stupid3, @stupid4, @stupid5)";
cmd.Parameters.AddWithValue("@stupid0", databaseLine);
cmd.Parameters.AddWithValue("@stupid1", counter);
cmd.Parameters.AddWithValue("@stupid2", databaseValue);
cmd.Parameters.AddWithValue("@stupid3", DateTime.Now);
cmd.Parameters.AddWithValue("@stupid4", assignDate);
cmd.Parameters.AddWithValue("@stupid5", complete);
cmd.Connection = connection;
cmd.ExecuteNonQuery();
connection.Close();
}
catch (MySqlException ex)
{
txtExercise.Text = ex.ToString();
}
}
推荐阅读
- javascript - 对 Json 值进行数学运算,在 For 循环中不起作用
- dart - 如何在颤动中管理图像上的点赞按钮
- node.js - AWS S3 SDK - 将版本化对象复制到同一个存储桶中
- css - 如何在不使用最小错误中的宽类的情况下摆脱最大宽度 1280?
- haskell - 尝试在 Xmonad 中使用 ManagerDocks 时出现模糊的“无法匹配预期类型”错误
- winapi - win32 WM_NOTIFY 与 WM_COMMAND
- c# - C#:如何将 RAW 图像(格式:rgb565)加载到位图中?
- aws-lambda - 如何通过 AWS Lambda python 代码读取图像?
- javascript - Vue在不知道数组名称的情况下单击时从数组中删除项目?
- swift - 有没有办法改变一组按钮上的文本输入?