为什么会出现这个错误
//页面代码(dlComment是DataList)
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
DisplayComment(int.Parse(Request.QueryString["Id"].ToString()));
}
}
protected void DisplayComment(int id)
{
dlComment.DataSource =BooksRatingsManager.GetBookRatingsInfo(id);
dlComment.DataBind();
}
//业务逻辑
public static List<BooksRatings> GetBookRatingsInfo(int bid)
{
return BooksRatingsService.GetBookRatingsInfo(bid);
}
//数据层
public static List<BooksRatings> GetBookRatingsInfo(int bid)
{
string sql=String.Format("SELECT * FROM BookRatings WHERE BookId='{0}'",bid);
return BooksRatingsService.GetBooksRatingsBySql(sql);
} private static List<BooksRatings> GetBooksRatingsBySql(string sql)
{
List<BooksRatings> list = new List<BooksRatings>();
DataTable table = DBHelper.GetDataSet(sql);
foreach (DataRow row in table.Rows)
{
BooksRatings br=new BooksRatings ();
br.Bookid=(int)row["Bookid"];
br.Comment=(string)row["Comment"];
br.Id=(int)row["Id"];
br.Rating=(int)row["Rating"];
list.Add(br);
}
return list;
}
}
}
//页面代码(dlComment是DataList)
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
DisplayComment(int.Parse(Request.QueryString["Id"].ToString()));
}
}
protected void DisplayComment(int id)
{
dlComment.DataSource =BooksRatingsManager.GetBookRatingsInfo(id);
dlComment.DataBind();
}
//业务逻辑
public static List<BooksRatings> GetBookRatingsInfo(int bid)
{
return BooksRatingsService.GetBookRatingsInfo(bid);
}
//数据层
public static List<BooksRatings> GetBookRatingsInfo(int bid)
{
string sql=String.Format("SELECT * FROM BookRatings WHERE BookId='{0}'",bid);
return BooksRatingsService.GetBooksRatingsBySql(sql);
} private static List<BooksRatings> GetBooksRatingsBySql(string sql)
{
List<BooksRatings> list = new List<BooksRatings>();
DataTable table = DBHelper.GetDataSet(sql);
foreach (DataRow row in table.Rows)
{
BooksRatings br=new BooksRatings ();
br.Bookid=(int)row["Bookid"];
br.Comment=(string)row["Comment"];
br.Id=(int)row["Id"];
br.Rating=(int)row["Rating"];
list.Add(br);
}
return list;
}
}
}
{
DisplayComment(int.Parse(Request.QueryString["Id"].ToString()));
}
foreach (DataRow row in table.Rows)
{
BooksRatings br=new BooksRatings ();
br.Bookid=(int)row["Bookid"];
br.Comment=(string)row["Comment"];
br.Id=(int)row["Id"];
br.Rating=(int)row["Rating"];
list.Add(br);
}
---------------
这些也一样,首先要判断这个Table的Rows.count>0
自己好好检查检查吧
这个地方可能有问题,你必须能够保证request.querystring["id"]有值,所以你要先判断一下!!