String.CompareOrdinal Method (String, Int32, String, Int32, Int32)


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Compares substrings of two specified String objects by evaluating the numeric values of the corresponding Char objects in each substring.

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

public static int CompareOrdinal(
	string strA,
	int indexA,
	string strB,
	int indexB,
	int length


Type: System.String

The first string to use in the comparison.

Type: System.Int32

The starting index of the substring in strA.

Type: System.String

The second string to use in the comparison.

Type: System.Int32

The starting index of the substring in strB.

Type: System.Int32

The maximum number of characters in the substrings to compare.

Return Value

Type: System.Int32

A 32-bit signed integer that indicates the lexical relationship between the two comparands.



Less than zero

The substring in strA is less than the substring in strB.


The substrings are equal, or length is zero.

Greater than zero

The substring in strA is greater than the substring in strB.

Exception Condition

strA is not null and indexA is greater than strA.Length.


strB is not null andindexB is greater than strB.Length.


indexA, indexB, or length is negative.

The indexA, indexB, and length parameters must be nonnegative.

The number of characters compared is the lesser of the length of strA less indexA, the length of strB less indexB, and length.

This method performs a case-sensitive comparison using ordinal sort rules. For more information about word, string, and ordinal sorts, see System.Globalization.CompareOptions. To perform a case-insensitive comparison using ordinal sort rules, call theCompare(String, Int32, String, Int32, Int32, StringComparison)method with the comparisonType argument set toStringComparison.OrdinalIgnoreCase.

Because CompareOrdinal(String, String) is a static method, strA and strB can be null. If both values are null, the method returns 0 (zero), which indicates that strA and strB are equal. If only one of the values is null, the method considers the non-null value to be greater.

This following example demonstrates that CompareOrdinal and Compare use different sort orders.

using System;
using System.Globalization;

class Test 
	public static void Main(String[] args) 
	String strLow = "abc";
	String strCap = "ABC";
	String result = "equal to ";
	int x = 0;
	int pos = 1;

// The Unicode codepoint for 'b' is greater than the codepoint for 'B'.
	x = String.CompareOrdinal(strLow, pos, strCap, pos, 1);
	if (x < 0) result = "less than";
	if (x > 0) result = "greater than";
	Console.WriteLine("CompareOrdinal(\"{0}\"[{2}], \"{1}\"[{2}]):", strLow, strCap, pos);
	Console.WriteLine("   '{0}' is {1} '{2}'", strLow[pos], result, strCap[pos]);

// In U.S. English culture, 'b' is linguistically less than 'B'.
	x = String.Compare(strLow, pos, strCap, pos, 1, false, new CultureInfo("en-US"));
	if (x < 0) result = "less than";
	else if (x > 0) result = "greater than";
	Console.WriteLine("Compare(\"{0}\"[{2}], \"{1}\"[{2}]):", strLow, strCap, pos);
	Console.WriteLine("   '{0}' is {1} '{2}'", strLow[pos], result, strCap[pos]);

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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