I would like to know the fastest/easiest way to check if a CheckBoxList control has any checked items or not, I'm talking about an entire checkbox list as a whole, not a single checkbox.
This one should help:
bool isAnySelected = checkBoxList.Items.Any(i => i.Selected);
.Any
is a Linq extension method, so you will need the System.Linq
or .System.Linq.Extensions
reference (can't remember which) in your code-behind.
The Linq extension method is neat, but you can also just check the SelectedIndex:
bool isAnySelected = CheckBoxList1.SelectedIndex != -1;
If nothing is checked, the SelectedIndex is -1.
For anyone coming here 5 years after the selected answer, the Items collection is not enumerable therefore .Any(...)
will not work. You can, however, do the following:
If cblCheckboxList.Items.Cast(Of ListItem).Any(Function(x) x.Selected) then...
The selected answer is great but now you can simply modify the code by adding OfType function. check the following:
bool isAnySelected = checkBoxList.Items.OfType<ListItem>().Any(i =>
i.Selected);
I hope this helps.
来源:https://stackoverflow.com/questions/3486847/checking-if-checkboxlist-has-any-selected-values