[RESOLVED] foreach skip items

hi all,

I want to remove some selected items on a list. So I use a foreach loop.

Code:

---


foreach (int i in MyList.SelectedIndices)
{
    MyList.Items.RemoveAt(i);
}

---

But it remove elements one by one, in odd pattern. Can somebody tell me what's wrong here.

thanks a lot

foreach is only used for READ-ONLY stuff, as far I know.
You should use a general "for int i" construction to edit any members.

But you have got a simple problem:
By deleting one item of your list, the in indices of the other elements are being reordered and changes so..
if you delete the next item with a selected index now,
you just delete a complete wrong item in your list.

Ya, that's true. What I have do there is delete from the last element. Now it's fixed. When I use foreach loop, there is an index conflict take place.

DO NOT user foreach or for loop if the counter that determines when to exit the loop is changing during the loop.

To solve that problem either use a while loop:

Code:

---

int i=0;
while(i < myList.Items.Count)
{
      if(myList.Items[i].ShouldBeRemoved())
        myList.Items.RemoveAt(i);
      else
        i++;
}

---

(in your case:

Code:

---

while(myList.Items.Count > 0)
{
    myList.Items.RemoveAt(0);
}

---

)
OR a for loop from end to start:

Code:

---

for(i=myList.Count-1;i>=0;i--)
    if(myList.Items[i].ShouldBeRemoved())
      myList.Items.RemoveAt(i);

---

(In your case the if statement is not needed)

Thanks a lot. I've done it. Thanks for all comments.