你的问题有三个部分:
- 如何在GridView中添加DropDownList?
- 如何从GridView内的DropDownList获取所选项?
- 如何计算值并在GridView中显示?
以下是我们可以执行的步骤。首先在页面中添加此标记。我添加了一个产品名称列,以使其更好看:
<asp:GridView ID="GridView1" AutoGenerateColumns="false" runat="server" OnRowDataBound="GridView1_RowDataBound">
<Columns>
<asp:BoundField DataField="Name" HeaderText="Name" />
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:DropDownList ID="ddlQuantity" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ddlQuantity_SelectedIndexChanged"></asp:DropDownList>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Price">
<ItemTemplate>
<asp:Label ID="lblPrice" Text='<%#Eval("Price") %>' runat="server" ></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Amount">
<ItemTemplate>
<asp:Label ID="lblAmount" Text="0.00" runat="server" ></asp:Label>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
如何在GridView中添加DropDownList
在Page_Load()方法中填充GridView(我使用了一个产品列表):
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
GridView1.DataSource = new List<Product>()
{
new Product{ID=1, Name="Paper", Price=7.99M},
new Product{ID=2, Name="Pen", Price=14.99M},
new Product{ID=3, Name="Pencil", Price=1.99M}
};
GridView1.DataBind();
}
}
这将触发GridView
的RowDataBound
事件。在事件处理方法中,我们将绑定每一行中的DropDownList
,如下所示:
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
var ddl = e.Row.FindControl("ddlQuantity") as DropDownList;
if (ddl != null)
{
ddl.DataSource = new List<string>() { "0", "1", "2", "3", "4" };
ddl.DataBind();
}
}
}
如何从GridView中的DropDownList获取所选项以及如何计算值并在GridView中显示
当您更改DropDownList中的任何选择时,它的SelectedIndexChange事件将触发。在该事件方法中,我们可以找到哪个DropDownList已更改以及它的“NamingContainer”-包含它的GridView行:
protected void ddlQuantity_SelectedIndexChanged(object sender, EventArgs e)
{
GridViewRow gvr = ((DropDownList)sender).NamingContainer as GridViewRow ;
if (gvr != null)
{
decimal price = 0.00M;
int quantity = 0;
var ddlQuantity = gvr.FindControl("ddlQuantity") as DropDownList;
var lblPrice = gvr.FindControl("lblPrice") as Label;
var lblAmount = gvr.FindControl("lblAmount") as Label;
if (ddlQuantity != null && lblPrice != null && lblAmount != null)
{
int.TryParse(ddlQuantity.SelectedValue, out quantity);
decimal.TryParse(lblPrice.Text, out price);
lblAmount.Text = (price * quantity).ToString();
}
}
}
这是最终的结果:
你可以在这里下载测试项目。