填充的列表框像这样:列表框Selected.value抛出空例外
if (ds != null)
{
ListPreviousRecords.Items.Clear();
ListPreviousRecords.DataSource = ds;
ListPreviousRecords.DataTextField = "Date";
ListPreviousRecords.DataValueField = "ID";
ListPreviousRecords.DataBind();
}
获取选定值:
protected void ListPreviousRecords_OnSelectedIndexChanged(object sender, EventArgs e)
{
if(ListPreviousRecords.SelectedItem.Value != "")
{
int mySelectedValue = int.Parse(ListPreviousRecords.SelectedItem.Value);// throwing null exception
loadPreviousDetails(mySelectedValue);
}
}
检查,如果SelectedItem.Value是。否则,你可能会遇到你的if语句,其中的空值导致你的异常。 – 2013-03-19 10:46:39