IComparable.CompareTo Method

Tuple<T1, T2>.IComparable.CompareTo Method

[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]

Compares the current Tuple<T1, T2> object to a specified object and returns an integer that indicates whether the current object is before, after, or in the same position as the specified object in the sort order.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

int IComparable.CompareTo(
	Object obj


Type: System.Object
An object to compare with the current instance.

Return Value

Type: System.Int32
A signed integer that indicates the relative position of this instance and obj in the sort order, as shown in the following table.



A negative integer

This instance precedes obj.


This instance and obj have the same position in the sort order.

A positive integer

This instance follows obj.




obj is not a Tuple<T1, T2> object.

This member is an explicit interface member implementation. It can be used only when the Tuple<T1, T2> instance is cast to an IComparable interface.

This method provides the IComparable.CompareTo implementation for the Tuple<T1, T2> class. Although the method can be called directly, it is most commonly called by the default overloads of collection sorting methods, such as Array.Sort(Array), to order the members of a collection.

Caution noteCaution:

The Tuple<T1, T2>.IComparable.CompareTo method is intended for use in sorting operations. It should not be used when the primary purpose of a comparison is to determine whether two objects are equal. To determine whether two objects are equal, call the Equals method.

The Tuple<T1, T2>.IComparable.CompareTo method uses the Comparer<T>.Default comparer.

The following example creates an array of Tuple<T1, T2> objects that consist of a student's name and test score. It displays the component of each tuple in the array in unsorted order, sorts the array, and then calls ToString to display the value of each tuple in sorted order. The output shows that the array has been sorted by its first component. Note that the example does not directly call the IComparable.CompareTo(Object) method. This method is called implicitly by the Sort(Array) method for each element in the array.

Windows Phone OS

Supported in: 8.1, 8.0

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