int i; for (i = 0; i < ListBox1.Items.Count; i++) if (TextBox1.Text.Trim() == ListBox1.Items[i].Value) { Response.Write("<script>alert('已存在此项');</script>"); return; } ListBox1.Items.Add(TextBox1.Text.Trim()); Response.Write("<script>alert('添加成功');</script>");
{
listBox1.Items.Add("Item " + x.ToString());
}
listview1.items(n).subitems.add("新行第二列字符");
listview1.items(n).subitems.add("新行第三列字符");
for (i = 0; i < ListBox1.Items.Count; i++)
if (TextBox1.Text.Trim() == ListBox1.Items[i].Value)
{
Response.Write("<script>alert('已存在此项');</script>");
return;
}
ListBox1.Items.Add(TextBox1.Text.Trim());
Response.Write("<script>alert('添加成功');</script>");