如何从数据列表中获取ID? [英] How to get the id from datalist ?

问题描述

我有包含项目的数据列表

在每个项目下都有一个链接

I have datalist which has items

and under every item there is a link

<asp:LinkButton runat="server" ID="Add" OnClick="lnkAdd_Click"
                Text="Add to cart" CommandName="Add" />

我为此链接创建事件处理程序

I make event handler for this link like that

protected void lnkAdd_Click(object sender, EventArgs e)
  {
    //  int ProId =Convert.ToInt32(((Label)ListView_Products.Controls[0].FindControl("IDLabel")).Text);

      int ProductID = int.Parse("ItemID");
      AddToShoppingCart(ProductID);
      Response.Redirect("ShoppingCartaspx.aspx");
  }

我的问题
如何从数据列表中获取productID?
它给我错误null引用

在此先感谢.

my question
how to get productID from datalist ???
it gives me error null reference

thanks in advance .

推荐答案

尝试:
以下将ItemID绑定到LinkBut​​ton的CommandArgument.

Try:
Following binds the ItemID to the CommandArgument of the LinkButton.

<asp:LinkButton ID="LinkButton1" runat="server" Text="Add to cart"

   OnClick="LinkButton1_Click" CommandArgument='<%# Eval("ItemID") %>' />

然后，您可以在后面的代码中像这样检索它:

You can then retrieve it like this in the code behind:

protected void LinkButton1_Click(object sender, EventArgs e)
{
  LinkButton myButton = sender as LinkButton;
  if (myButton != null)
  {
     int id = Convert.ToInt32(myButton.CommandArgument);
  }
}

发送方持有对触发事件处理程序的LinkBut​​ton的引用.
您可以将对象转换为LinkBut​​ton，然后检索其CommandArgument并将其转换为int.

The sender holds a reference to the LinkButton that triggered the event handler.
You can cast the object into a LinkButton and then retrieve its CommandArgument and cast that into an int.

使用此语法

Use This Syntax

DataListItem dl = ((DataListItem)(DataControlFieldCell(((ImageButton)sender).Parent).Parent));

Int32 var = Convert.Toint32(((Label)dl.FindControl("lbl")).ToString());

如果许多产品并且想要启用多选功能，那么只需在for循环中使用下面的代码即可.

If you have many products and want to make multi-selection enable, then just use below code inside for loop.

Label lblID = (Label)DList1.Items[i].FindControl("IDLabel");
Int32 PID = Convert.ToInt32(lblID.ToString();

唯一的不同是
如有疑问，请回复.

约翰·巴特(John Bhatt)，
P.Yar.B Complex

Only Difference is that
Reply if some confusion.

John Bhatt,
P.Yar.B Complex

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