ImmutableList<T>.BinarySearch Method (Int32, Int32, T, IComparer<T>)


Searches a range of elements in the sorted list for an element using the specified comparer and returns the zero-based index of the element.

Namespace:   System.Collections.Immutable
Assembly:  System.Collections.Immutable (in System.Collections.Immutable.dll)

public int BinarySearch(
	int index,
	int count,
	T item,
	IComparer<T> comparer


Type: System.Int32

The zero-based starting index of the range to search.

Type: System.Int32

The length of the range to search.

Type: T

The object to locate. The value can be null for reference types.

Type: System.Collections.Generic.IComparer<T>

The comparer implementation to use when comparing elements, or null to use the default comparer.

Return Value

Type: System.Int32

The zero-based index of item in the sorted list, if item is found; otherwise, a negative number that is the bitwise complement of the index of the next element that is larger than item or, if there is no larger element, the bitwise complement of count.

Exception Condition

index is less than 0 or count is less than 0.


index and count do not denote a valid range in the list.


comparer is null, and the default comparer cannot find an comparer implementation for type T.

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