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Int32.CompareTo Method (Int32)

Compares this instance to a specified 32-bit signed integer and returns an indication of their relative values.

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

public int CompareTo(
	int value


Type: System.Int32

An integer to compare.

Return Value

Type: System.Int32
A signed number indicating the relative values of this instance and value.

Return Value


Less than zero

This instance is less than value.


This instance is equal to value.

Greater than zero

This instance is greater than value.



This method implements the System.IComparable<T> interface and performs slightly better than the Int32.CompareTo method because it does not have to convert the value parameter to an object.

Depending on your programming language, it might be possible to code a CompareTo method where the parameter type has fewer bits (is narrower) than the instance type. This is possible because some programming languages perform an implicit widening conversion that represents the parameter as a type with as many bits as the instance.

For example, suppose the instance type is Int32 and the parameter type is Byte. The Microsoft C# compiler generates instructions to represent the value of the parameter as an Int32, then generates a Int32.CompareTo method that compares the values of the Int32 instance and the Int32 parameter representation.

Consult your programming language's documentation to determine whether its compiler performs implicit widening conversions on numeric types.

The following example demonstrates the Int32.CompareTo(Int32) method. In addition to displaying the value returned by the method for four different comparisons, it converts the return value to a member of the custom Comparison enumeration, whose value it also displays.

using System;

enum Comparison {
   LessThan=-1, Equal=0, GreaterThan=1};

public class ValueComparison
   public static void Main()
      int mainValue = 16325;
      int zeroValue = 0;
      int negativeValue = -1934;
      int positiveValue = 903624;
      int sameValue = 16325;

      Console.WriteLine("Comparing {0} and {1}: {2} ({3}).",  
                        mainValue, zeroValue, 
                        (Comparison) mainValue.CompareTo(zeroValue));

      Console.WriteLine("Comparing {0} and {1}: {2} ({3}).",
                        mainValue, sameValue, 
                        (Comparison) mainValue.CompareTo(sameValue));

      Console.WriteLine("Comparing {0} and {1}: {2} ({3}).", 
                        mainValue, negativeValue, 
                        (Comparison) mainValue.CompareTo(negativeValue));

      Console.WriteLine("Comparing {0} and {1}: {2} ({3}).", 
                        mainValue, positiveValue, 
                        (Comparison) mainValue.CompareTo(positiveValue));
// The example displays the following output: 
//       Comparing 16325 and 0: 1 (GreaterThan). 
//       Comparing 16325 and 16325: 0 (Equal). 
//       Comparing 16325 and -1934: 1 (GreaterThan). 
//       Comparing 16325 and 903624: -1 (LessThan).

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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