CollectionBase.IList.IndexOf Method (Object)
Searches for the specified Object and returns the zero-based index of the first occurrence within the entire CollectionBase.
Assembly: mscorlib (in mscorlib.dll)
private abstract IndexOf : value:Object -> int private override IndexOf : value:Object -> int
Parameters
- value
-
Type:
System.Object
The Object to locate in the CollectionBase.
Return Value
Type: System.Int32The zero-based index of the first occurrence of value within the entire CollectionBase, if found; otherwise, -1.
Implements
IList.IndexOf(Object)This method performs a linear search; therefore, this method is an O(n) operation, where n is Count.
This method determines equality by calling Object.Equals.
Starting with the .NET Framework 2.0, this method uses the collection’s objects’ Equals and CompareTo methods on item to determine whether item exists. In the earlier versions of the .NET Framework, this determination was made by using the Equals and CompareTo methods of the item parameter on the objects in the collection.
Available since 10
.NET Framework
Available since 1.1