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C# 在MySql中使用where子句选择_C#_Mysql_Select_Visual Studio 2013_Where - Fatal编程技术网

C# 在MySql中使用where子句选择

C# 在MySql中使用where子句选择,c#,mysql,select,visual-studio-2013,where,C#,Mysql,Select,Visual Studio 2013,Where,是否可以从具有特定ID的表中选择数据?我知道它适用于更新,但select的代码是什么 我在visual Studio中使用c,我的目标是在只读文本框中显示详细信息 这应该可以 string Command = @"select corporateName, corporateAddress, corporateContact from corporatemembership where corporateI

是否可以从具有特定ID的表中选择数据?我知道它适用于更新,但select的代码是什么

我在visual Studio中使用c,我的目标是在只读文本框中显示详细信息

这应该可以

string Command = 
  @"select corporateName, 
           corporateAddress, 
           corporateContact 
      from corporatemembership 
     where corporateID = @CorpID;";

using (MySqlConnection myConnection = new MySqlConnection(ConnectionString))
{
    using (MySqlDataAdapter myDataAdapter = new MySqlDataAdapter(Command, myConnection))
    {
        myDataAdapter.SelectCommand.Parameters.Add(new MySqlParameter("@CorpID", CorpID.Text));
        DataTable dtResult = new DataTable();
        myDataAdapter.Fill(dtResult);
        corporateName.Text = dtResult.Rows[0]["corporateName"];
        corporateAddress.Text = dtResult.Rows[0]["corporateAddress"];
        corporateContact.Text = dtResult.Rows[0]["corporateContact"];
    }
}
可能您应该添加一些错误处理,并处理CorpID不存在的情况

更新另一种方法

string Command =
        @"select corporateName, 
                 corporateAddress, 
                 corporateContact 
            from corporatemembership 
            where corporateID = @CorpID;";
using (MySqlConnection mConnection = new MySqlConnection(ConnectionString))
{
    mConnection.Open();
    using (MySqlCommand cmd = new MySqlCommand(Command, mConnection))
    {
        cmd.Parameters.Add(new MySqlParameter("@CorpID", CorpID.Text));
        using (MySqlDataReader reader = cmd.ExecuteReader())
        {
            if (reader.Read())
            {
                corporateName.Text = (string)reader["corporateName"];
                corporateAddress.Text = (string)reader["corporateAddress"];
                corporateContact.Text = (string)reader["corporateContact"];
            }
        }
    }
}
是的,有可能, 您的sql字符串是正常的,除了最后一部分,您将编辑最后一部分

string corp=从corporatemembership中选择corporateName、corporateAddress、corporateContact,其中corporateID=+'+CorpID.Text+'

请试一试。
string Command =
        @"select corporateName, 
                 corporateAddress, 
                 corporateContact 
            from corporatemembership 
            where corporateID = @CorpID;";
using (MySqlConnection mConnection = new MySqlConnection(ConnectionString))
{
    mConnection.Open();
    using (MySqlCommand cmd = new MySqlCommand(Command, mConnection))
    {
        cmd.Parameters.Add(new MySqlParameter("@CorpID", CorpID.Text));
        using (MySqlDataReader reader = cmd.ExecuteReader())
        {
            if (reader.Read())
            {
                corporateName.Text = (string)reader["corporateName"];
                corporateAddress.Text = (string)reader["corporateAddress"];
                corporateContact.Text = (string)reader["corporateContact"];
            }
        }
    }
}