我正在创建这个函数,我正在创建更新我的数据库。更新教师成员似乎完美地工作,而更新人员表则没有。我假设MySQL Query不适合更新人员表。
其他信息:我的代码现在已连接到GUI模拟器,用于测试目的。更新字符串@Id ..它只是为了选择我想要更改的ID ..
public static void Update(string update,string fName, string lName, string DOB, string postCode, string address, string phoneNumber,
bool isTenured, string qualifications, string previousEmployment)
{
MySqlConnection conn;
MySqlCommand cmd;
string sql = "UPDATE person SET firstName = @FirstName , lastName = @LastName, DOB = @DOB, phoneNumber = @PhoneNumber, address = @Address, postCode = @PostCode WHERE ID =@Id;";
GetConnection(out conn, out cmd, sql);
try
{
cmd.Parameters.AddWithValue("@Id", update);
cmd.Parameters.AddWithValue("@FirstName", fName);
cmd.Parameters.AddWithValue("@LastName", lName);
cmd.Parameters.AddWithValue("@DOB", DOB);
cmd.Parameters.AddWithValue("@PhoneNumber", phoneNumber);
cmd.Parameters.AddWithValue("@Address", address);
cmd.Parameters.AddWithValue("@PostCode", postCode);
long id = (long)cmd.LastInsertedId;
sql = "UPDATE facultymember SET isTenured = @IsTenured, qualifications = @Qualifications, previousEmployment = @PreviousEmployment WHERE Person_personID=@Id";
cmd = new MySqlCommand(sql, conn);
cmd.Parameters.AddWithValue("@IsTenured", isTenured);
cmd.Parameters.AddWithValue("@Qualifications", qualifications);
cmd.Parameters.AddWithValue("@PreviousEmployment", previousEmployment);
cmd.ExecuteNonQuery();
}
catch (NullReferenceException nre)
{
MessageBox.Show(nre.Message);
}
catch (Exception e)
{
MessageBox.Show(e.Message);
}
finally
{
try
{
MessageBox.Show("Updated");
cmd.Connection.Close();
conn.Close();
}
catch (Exception e)
{
MessageBox.Show(e.Message);
}
}
}
答案 0 :(得分:1)
您忘记在第二个SQL查询中添加@Id
参数。
sql = "UPDATE facultymember
SET isTenured = @IsTenured, qualifications = @Qualifications, previousEmployment = @PreviousEmployment
WHERE Person_personID=@Id";
// ^^^^
cmd = new MySqlCommand(sql, conn);
cmd.Parameters.AddWithValue("@IsTenured", isTenured);
cmd.Parameters.AddWithValue("@Qualifications", qualifications);
cmd.Parameters.AddWithValue("@PreviousEmployment", previousEmployment);
cmd.Parameters.AddWithValue("@Id", YourIdValue);
cmd.ExecuteNonQuery();
同时使用using
statement来处理您的MySqlConnection
和MySqlCommand
之类的内容;
using(MySqlConnection conn = new MySqlConnection(ConnectionString))
using(MySqlCommand cmd = conn.CreateCommand())
{
//
}