Collection<T>.IList.IndexOf(Object) Method
Definition
Determines the index of a specific item in the IList.
virtual int System.Collections.IList.IndexOf(System::Object ^ value) = System::Collections::IList::IndexOf;
int IList.IndexOf (object value);
abstract member System.Collections.IList.IndexOf : obj -> int
override this.System.Collections.IList.IndexOf : obj -> int
Function IndexOf (value As Object) As Integer Implements IList.IndexOf
Parameters
Returns
The index of value
if found in the list; otherwise, -1.
Implements
Exceptions
value
is of a type that is not assignable to the IList.
Remarks
This method determines equality using the default comparer Comparer<T>.Default. Comparer<T>.Default checks whether type T
implements System.IComparable<T> and uses that implementation, if available. If not, Comparer<T>.Default checks whether type T
implements System.IComparable. If type T
does not implement either interface, this method uses Object.Equals.
This method is an O(n
) operation, where n
is Count.