Removing

There are two ways you can remove all the instances of an element.

Remove

The Remove method will only remove the first occurrence of an element.

myArrayList.Remove("string"); 

while (myArrayList.IndexOf("remove this") >= 0) 
{ 
   myArrayList.Remove("remove this"); 
} 

RemoveAt

myArrayList.RemoveAt(1); 

Also this method does not generate an exception if the element you want to remove cannot be found.

RemoveRange