c# - System.Data.Objects.MaterializedDataRecord 不包含属性

Question

代码隐藏

    protected void RadGrid1_NeedDataSource(object sender, GridNeedDataSourceEventArgs e)
    {
        RadGrid1.DataSource = DbContext.students.Select("it.name,it.subject");
    }

    protected void RadGrid1_InsertCommand(object sender, GridCommandEventArgs e)
    {
        GridEditableItem item = e.Item as GridEditableItem;
        Hashtable values = new Hashtable();
        item.ExtractValues(values);
        student stdd = new student();
        item.UpdateValues(stdd);
        DbContext.AddTostudents(stdd);
        DbContext.SaveChanges();
    }

    protected void RadGrid1_UpdateCommand(object sender, GridCommandEventArgs e)
    {
        GridEditableItem item = e.Item as GridEditableItem;
        int roll = (int)item.GetDataKeyValue("rollno");
        //int t = Int32.Parse(roll);
        student stdd = DbContext.students.Where(p => p.rollno == roll).FirstOrDefault();
        item.UpdateValues(stdd);
        //DbContext.AddTostudents(stdd);
        DbContext.SaveChanges();

    }

    protected void RadGrid1_DeleteCommand(object sender, GridCommandEventArgs e)
    {
        GridDataItem item = e.Item as GridDataItem;
        int roll=(int)item.GetDataKeyValue("rollno");
        student stdd = DbContext.students.Where(p => p.rollno == roll).FirstOrDefault();
        DbContext.DeleteObject(stdd);
        DbContext.SaveChanges();

    }

并收到类似 DataBinding 的错误:“System.Data.Objects.MaterializedDataRecord”不包含名称为“rollno”的属性。我的表名称为学生，列名称为-rollno、名称、主题。

Answer 1

你只选择了name和subject字段，尝试添加rollno字段再试一次

DbContext.students.Select("it.name,it.subject,it.rollno");