通过Coading完成分页时从gridview获取价值的问题 [英] problem in getting value from gridview when paging is done by coading

问题描述

朋友，

我启用分页并使用以下事件

Friends,

I enable paging and use following event

protected void gvReprintEmail_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        gvReprintEmail.PageIndex = e.NewPageIndex;
        DataTable dt1 = (DataTable)Session["dt"];
        gvReprintEmail.DataSource = dt1;
        gvReprintEmail.DataBind();
    }

但是当我想从gridview中获取任何值时，我就得到了异常，因为在rowcommand事件中，我从当前事件中获取了row的值.因此有一个异常，例如索引超出范围.必须为非负数并且小于集合的大小."

我使用的页面大小为3，在第二页和之后的页面中，出现了这样的异常.

这是gridview的列之一

< itemtemplate>
< asp:标签runat ="server" ID ="lblMessage" Text =''<％#Server.HtmlDecode(Eval("Body").ToString())％>''>




以下是发生异常的rowcommand事件
在第一页中这没有问题，但是在随后的页面中，当我单击gridview中给出的链接时，将出现异常

受保护的void gvReprintEmail_RowCommand(object sender，GridViewCommandEventArgs e)
{
int索引= Convert.ToInt32(e.CommandArgument); <-在第二页的第一行上，我单击，因此索引将为3，因为页面大小为3

标签lbl =(标签)gvReprintEmail.Rows [index] .FindControl("lblMessage"); <-exception
Session ["SentDate"] = gvReprintEmail.Rows [index] .Cells [0] .Text;
Session ["Subject"] = gvReprintEmail.Rows [index] .Cells [1] .Text;
会话[消息"] = lbl.Text;
OpenNewWindow("PrintEmail.aspx");
}


请帮助我.在此先感谢.

But when i want to get any value from gridview then i got exception because in rowcommand event i get value of row from current event. So there is exception like "Index was out of range. Must be non-negative and less than the size of the collection."

I use page size 3 and in 2nd and afterward pages i got exception like this.

here is one of column of gridview

<itemtemplate>
<asp:Label runat="server" ID="lblMessage" Text=''<%# Server.HtmlDecode(Eval("Body").ToString()) %>'' >




following is rowcommand event where i got exception
in first page there is no problem in this, but afterwards page when i click link given in gridview then there will exception

protected void gvReprintEmail_RowCommand(object sender, GridViewCommandEventArgs e)
{
int index = Convert.ToInt32(e.CommandArgument); <--on 2nd page first row i click so index will be 3 because page size 3

Label lbl = (Label)gvReprintEmail.Rows[index].FindControl("lblMessage"); <--exception
Session["SentDate"] = gvReprintEmail.Rows[index].Cells[0].Text;
Session["Subject"] = gvReprintEmail.Rows[index].Cells[1].Text;
Session["Message"] = lbl.Text;
OpenNewWindow("PrintEmail.aspx");
}


Kindly help me. Thanks in advance.

推荐答案

查看此处:

private void BindData()
{
    string connectionString = "Server=localhost;" + 
           "Database=Northwind;Trusted_Connection=true";
    SqlConnection myConnection = new SqlConnection(connectionString);
    SqlCommand myCommand = new SqlCommand("usp_GetProducts", 
                                           myConnection);
    myCommand.CommandType = CommandType.StoredProcedure;
    myCommand.Parameters.AddWithValue("@startRowIndex", 
                                      currentPageNumber);
    myCommand.Parameters.AddWithValue("@maximumRows", PAGE_SIZE);
    myCommand.Parameters.Add("@totalRows", SqlDbType.Int, 4);
    myCommand.Parameters["@totalRows"].Direction = 
                       ParameterDirection.Output;
    SqlDataAdapter ad = new SqlDataAdapter(myCommand);
    DataSet ds = new DataSet();
    ad.Fill(ds);
    gvProducts.DataSource = ds;
    gvProducts.DataBind();
    // get the total rows 
    double totalRows = (int)myCommand.Parameters["@totalRows"].Value;
    lblTotalPages.Text = CalculateTotalPages(totalRows).ToString();
    lblCurrentPage.Text = currentPageNumber.ToString(); 
    if (currentPageNumber == 1)
    {
        Btn_Previous.Enabled = false;
        if (Int32.Parse(lblTotalPages.Text) > 0)
        {
            Btn_Next.Enabled = true;
        }
        else
            Btn_Next.Enabled = false;
    }
    else
    {
        Btn_Previous.Enabled = true;
        if (currentPageNumber == Int32.Parse(lblTotalPages.Text))
            Btn_Next.Enabled = false;
        else Btn_Next.Enabled = true; 
    }
}

计算表中的总行数

Calculate total rows in table

private int CalculateTotalPages(double totalRows)
{
    int totalPages = (int)  Math.Ceiling(totalRows / PAGE_SIZE);
    return totalPages; 
}

制作两个按钮(下一个/上一个)，然后单击它们调用此方法

Make two buttons(next/Previous) and call this method on their click

protected void ChangePage(object sender, CommandEventArgs e)
{
    
    switch (e.CommandName)
    {
        case "Previous":
            currentPageNumber = Int32.Parse(lblCurrentPage.Text) - 1;
            break; 
        case "Next":
            currentPageNumber = Int32.Parse(lblCurrentPage.Text) + 1; 
            break; 
    }
    BindData();
}

尝试以下链接:
http://www.dotnetcurry.com/ShowArticle.aspx?ID=339 [ ^ ]
http://msdn.microsoft.com/en-us/library/5aw1xfh3.aspx [ ^ ]

Try the following links:
http://www.dotnetcurry.com/ShowArticle.aspx?ID=339[^]
http://msdn.microsoft.com/en-us/library/5aw1xfh3.aspx[^]

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