Collection<T>.IList.IndexOf(Object) Collection<T>.IList.IndexOf(Object) 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);
Function IndexOf (value As Object) As Integer Implements IList.IndexOf

Parameters

value
Object Object Object

The Object to locate in the IList.

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.

Applies to