没有从LIST中删除的项目

Question

I have a list that I am using to hold a queue of commands.

I need to loop though each item of the queue, executing the commands, deleting them as it goes along.

The items weren't being deleted from the queue.

Here is a quick test code which doesn't work either:

Dim MyList As New List(Of String)

For i = 0 To 5
   MyList.Add(i)
Next
MsgBox(MyList.Count) 'returns 6

MyList.Remove(2)
MyList.Remove(4)

For i = 0 To MyList.Count - 1
   MsgBox(MyList(i)) 'pops up 6 times, including the 2 "deleted" ones.
Next
MsgBox(MyList.Count) 'still returns 6

The items don't get deleted.

Answer 1

In your MyList.Remove calls, do you mean to remove the value 2 or remove at the index of 2 ? If you meant to remove at the index, then use RemoveAt :

MyList.RemoveAt(2)

Otherwise, if your code is actually exactly as you've posted, then it should be working fine. I plugged this into a little console app, and it worked:

Sub Main()
    Dim MyList As New List(Of String)

    For i = 0 To 5
        MyList.Add(i)
        Console.WriteLine("i: {0}", i)
    Next
    Console.WriteLine("MyList.Count: {0}", MyList.Count)

    MyList.Remove(2)
    MyList.Remove(4)

    For i = 0 To MyList.Count - 1
        Console.WriteLine("MyList({0}): {1}", i, MyList(i))
    Next
    Console.WriteLine("MyList.Count: {0}", MyList.Count)
    Console.Read()
End Sub

Output:

i: 0
i: 1
i: 2
i: 3
i: 4
i: 5
MyList.Count: 6
MyList(0): 0
MyList(1): 1
MyList(2): 3
MyList(3): 5
MyList.Count: 4