private OleDbConnection cnn = null;
        private OleDbCommand cmm = null;
        private OleDbDataAdapter sda = null;
        private OleDbParameter sp = null;
        private DataSet ds = null;
        public frmStu()
 private void btnAdd_Click(object sender, EventArgs e)
        {
            cmm = new OleDbCommand("INSERT INTO stu VALUES(@stuNo,@stuName,@stuScore)",cnn);
            sda = new OleDbDataAdapter();
            sda.InsertCommand = cmm;
            sp = sda.InsertCommand.Parameters.Add("@stuNo", null);
            sp.SourceColumn = "stuNo";
            sp.SourceVersion = DataRowVersion.Current;
            sp = sda.InsertCommand.Parameters.Add("@stuName", null);
            sp.SourceColumn = "stuName";
            sp.SourceVersion = DataRowVersion.Current;
            sp = sda.InsertCommand.Parameters.Add("@stuScore", null);
            sp.SourceColumn = "stuScore";
            sp.SourceVersion = DataRowVersion.Current;
            
            sda.Update(ds, "stu");
        }
        private void btnUpdate_Click(object sender, EventArgs e)
        {
            cmm = new OleDbCommand("UPDATE stu SET stuName = @stuName,stuScore = @stuScore WHERE stuNo = @stuNo", cnn);
            sda = new OleDbDataAdapter();
            sda.UpdateCommand = cmm;
            sp = sda.UpdateCommand.Parameters.Add("@stuNo", null);
            sp.SourceColumn = "stuNo";
            sp.SourceVersion = DataRowVersion.Original;
            sp = sda.UpdateCommand.Parameters.Add("@stuName", null);
            sp.SourceColumn = "stuName";
            sp.SourceVersion = DataRowVersion.Current;
            sp = sda.UpdateCommand.Parameters.Add("@stuScore", null);
            sp.SourceColumn = "stuScore";
            sp.SourceVersion = DataRowVersion.Current;

            sda.Update(ds, "stu");
        }
这是guoxhvip给我发的程序上的代码　可我用的是ACCESS 改了自己会改的 但之后就出现错误了
谁知道我哪里出现错误了?

什么错 不管什么数据库感觉都大同小异

看看你的OleDbConnection对象实例化了吗?还有OleDbCommand对象与Connection绑定了吗?光看上面的代码肯定会出错的.

OleDbConnection 对象没有实例化吧.

try
            {
                string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=student.mdb";
                OleDbConnection cnn = new OleDbConnection(strConn);
                cnn.Open();

                cmm = new OleDbCommand("SELECT * FROM stu", cnn);
                sda = new OleDbDataAdapter();
                sda.SelectCommand = cmm;
                ds = new DataSet();
                sda.Fill(ds, "stu");
 
 这是LOAD 的代码

我的就这么多了 我也弄不清楚是那错了  希望高手能帮帮忙

... 图片怎么串

查看一下你的student.mdb数据库的位置，你的connection类实例化时读的是相对路径的数据库文件，看一下是否存在这个文件？