ASP/ c# - Sql连接与更新

本文关键字:连接 更新 Sql ASP | 更新日期: 2023-09-27 17:53:07

    sql connectie
    string KlasconnectionString = @"DataSource=RICHARD'MSSQLSERVER12;Initial Catalog=MojoGegevens;Integrated Security=True";
    // verbinding 
    SqlDataAdapter DA = new SqlDataAdapter(sql, KlasconnectionString);
    DataSet DS = new DataSet();
    sql += "update tblOpmaak set Themakleur = 'red'";
    SqlConnection conn = new SqlConnection(KlasconnectionString);
    conn.Open();
    SqlCommand Cmd = new SqlConnection(sql, conn);
    Cmd.ExecuteNonQuery();
    conn.Close();

它给出了一个错误在"conn"的行:SqlCommand Cmd = new SqlConnection(sql, conn);

ASP/ c# - Sql连接与更新

通过使用这行代码(SqlCommand Cmd = new SqlConnection(sql, conn);)你要做的是创建一个新的连接并将其分配给SqlCommand,这样的分配是无效的,不允许的,这就是为什么它抛出错误。您可以使用以下行创建命令:

 SqlCommand Cmd = new SqlCommand (sql, conn);

And a Small advice for you;在where子句中指定条件,否则更新将影响所有行(如果要更新所有行,请保留)

您正在使用SqlCommand。所以你不能用New SqlConnection。你应该使用New SqlCommand

SqlCommand Cmd = new SqlCommand (sql, conn);

变化

 SqlCommand Cmd = new SqlConnection(sql, conn);

SqlCommand Cmd = new SqlCommand(sql, conn);
SqlConnection con = new SqlConnection(@"DataSource=RICHARD'MSSQLSERVER12;Initial Catalog=MojoGegevens;Integrated Security=True");
    con.Open();
    sql += "update tblOpmaak set Themakleur = 'red'";
    SqlDataAdapter DA = new SqlDataAdapter(sql, con);
    DataSet DS = new DataSet();
    SqlCommand Cmd = new SqlConnection(sql, conn);
    Cmd.ExecuteNonQuery();
    con.Close();