Source. Index Of(Object) Method
Searches for the specified object and returns the index of the first occurrence within the entire list.
public: virtual int IndexOf(System::Object ^ value);
public virtual int IndexOf (object value);
abstract member IndexOf : obj -> int override this.IndexOf : obj -> int
Public Overridable Function IndexOf (value As Object) As Integer
The zero-based index of the first occurrence of the
value parameter; otherwise, -1 if
value is not in the list.
Although the implementation is dependent on the underlying list's
IndexOf method, typically the following characteristics apply:
The List is searched starting at the first element and ending at the last element.
The underlying method performs a linear search; therefore, the average execution time is proportional to the value of the Count property.
The underlying method determines equality by calling the Equals method.