c# - 在插入期间增加一个 int

Question

我试图在插入期间从 c# .net 页面递增 MS Access 表中的整数。

尝试以下操作时出现语法错误。还不确定我是否应该使用 ExecuteNonQuery() ？

OleDbCommand cmd = new OleDbCommand("INSERT INTO tblTarget(target,ref) VALUES(@target,(SELECT MAX(ref)+1 FROM tblTarget)", conn);

cmd.Parameters.AddWithValue("@target", TextTitle.Text);
conn.Open();
cmd.ExecuteNonQuery();
conn.Close();

Answer 1

你在 tblTarget 之后错过了一个括号:

OleDbCommand cmd = 
    new OleDbCommand("INSERT INTO tblTarget(target,ref) VALUES(@target,(SELECT MAX(ref)+1 FROM tblTarget))", conn);

这里是对您的代码的一些回顾，尝试使用 using图案:

using(var conn = new Connection())
{
    conn.Open();
    string sql = "INSERT INTO tblTarget(target,ref) VALUES(@target,(SELECT MAX(ref)+1 FROM tblTarget))";
    OleDbCommand cmd = new OleDbCommand(sql, conn);

    cmd.Parameters.AddWithValue("@target", TextTitle.Text);

    cmd.ExecuteNonQuery();
}