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IListExtensionMethodsBinarySearchT Method
Searches for the element specified in the sorted list specified using binary search http://en.wikipedia.org/wiki/Binary_search. The algorithm is re-implemented here to be able to search in any sorted IList implementing data structure (.NET's BCL only implements BinarySearch on arrays and List(Of T). If no IComparer(Of T) is available, try using Algorithmia's ComparisonBasedComparer,

Namespace:  SD.Tools.BCLExtensions.CollectionsRelated
Assembly:  SD.Tools.BCLExtensions (in SD.Tools.BCLExtensions.dll) Version: 1.1.1
Syntax
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public static int BinarySearch<T>(
	this IList sortedList,
	T element,
	IComparer<T> comparer
)

Parameters

sortedList
Type: System.CollectionsIList
The sorted list.
element
Type: T
The element.
comparer
Type: System.Collections.GenericIComparerT
The comparer.

Type Parameters

T

Return Value

Type: Int32
The index of the element searched or the bitwise complement of the index of the next element that is larger than element or if there is no larger element the bitwise complement of Count. Bitwise complements have their original bits negated. Use the '~' operator in C# to get the real value. Bitwise complements are used to avoid returning a value which is in the range of valid indices so callers can't check whether the value returned is an index or if the element wasn't found. If the value returned is negative, the bitwise complement can be used as index to insert the element in the sorted list to keep the list sorted

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IList. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).
Remarks
Assumes that sortedList is sorted ascending. If you pass in a descending sorted list, be sure the comparer is adjusted as well.
See Also