List(Of T).FindIndex Method (Int32, Predicate(Of T))
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the first occurrence within the range of elements in the List(Of T) that extends from the specified index to the last element.
Assembly: mscorlib (in mscorlib.dll)
'Declaration Public Function FindIndex ( _ startIndex As Integer, _ match As Predicate(Of T) _ ) As Integer
Parameters
- startIndex
- Type: System.Int32
The zero-based starting index of the search.
- match
- Type: System.Predicate(Of T)
The Predicate(Of T) delegate that defines the conditions of the element to search for.
Return Value
Type: System.Int32The zero-based index of the first occurrence of an element that matches the conditions defined by match, if found; otherwise, –1.
| Exception | Condition |
|---|---|
| ArgumentNullException | match is Nothing. |
| ArgumentOutOfRangeException | startIndex is outside the range of valid indexes for the List(Of T). |
The List(Of T) is searched forward starting at startIndex and ending at the last element.
The Predicate(Of T) is a delegate to a method that returns true if the object passed to it matches the conditions defined in the delegate. The elements of the current List(Of T) are individually passed to the Predicate(Of T) delegate.
This method performs a linear search; therefore, this method is an O(n) operation, where n is the number of elements from startIndex to the end of the List(Of T).