打電話警告我有一個下拉列表和列表框都asp.net控制從代碼隱藏
我試圖阻止用戶duplciate項目添加到列表框控件
我能阻止它,但我想以顯示DIV或警報框說:「不允許複製姓名」
protected void btn_AddRecipientAction_OnClick(object sender, EventArgs e)
{
if (Convert.ToInt32(this.ddlRecipient.SelectedValue) > 0)
{
if (ddlRecipient.Text.Length > 0)
{
//var items = new System.Collections.ArrayList(this.lstRecipient.Items);
for(var i = lstRecipient.Items.Count - 1; i >= 0; --i)
{
if (lstRecipient.Items[i].Text == ddlRecipient.SelectedItem.Text)
{
lstRecipient.Items.RemoveAt(i);
**//alert("duplicate entry not allowed")
//div display the message and disappears after few seconds?**
}
}
ListItem newList = new ListItem();
newList.Text = ddlRecipient.SelectedItem.Text;
newList.Value = ddlRecipient.SelectedValue;
this.lstRecipient.Items.Add(newList);
}
}
}
如何在提交頁面之前在客戶端進行驗證? – 2010-07-26 19:08:19