Tuple(Of T1).IStructuralComparable.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(Of T1) object to a specified object by using a specified comparer, 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.
Assembly: mscorlib (in mscorlib.dll)
'Declaration Private Function CompareTo ( _ other As Object, _ comparer As IComparer _ ) As Integer Implements IStructuralComparable.CompareTo
Parameters
- other
- Type: System.Object
An object to compare with the current instance.
- comparer
- Type: System.Collections.IComparer
An object that provides custom rules for comparison.
Return Value
Type: System.Int32A signed integer that indicates the relative position of this instance and other in the sort order, as shown in the following table.
Value | Description |
|---|---|
A negative integer | This instance precedes other. |
Zero | This instance and other have the same position in the sort order. |
A positive integer | This instance follows other. |
Implements
IStructuralComparable.CompareTo(Object, IComparer)| Exception | Condition |
|---|---|
| ArgumentException | other is not a Tuple(Of T1) object. |
Although this method can be called directly, it is most commonly called by collection sorting methods that include IComparer parameters to order the members of a collection. For example, it is called by the Array.Sort(Array, IComparer) method.
Caution: |
|---|
The IStructuralComparable.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 IStructuralEquatable.Equals method. |
The following example defines a generic class named DescendingComparer that implements the IComparer(Of T) interface. DescendingComparer sorts objects in descending rather than ascending order by reversing the value returned by the default comparer for a particular type. An instance of the generic DescendingComparer class is then passed to the Array.Sort(Array, IComparer) method to sort an array of Tuple(Of T1) objects in descending order. Note that the example does not directly call the IStructuralComparable.CompareTo method. This method is called implicitly by the Array.Sort(Array, IComparer) method for each element in the array.
Caution: