Locale-Sensitive String Comparison

Internationalization Module User's Guide
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6.2 Locale-Sensitive String Comparison

In the Internationalization Module, RWUCollator performs locale-sensitive string comparison. Each RWUCollator is associated with an RWULocale at construction time, in order to take language-specific conventions into account. For example.

RWULocale myLocale("de");
RWUCollator myCollator(myLocale);

If no locale is specified, then the current default locale is used. The locale specifies the default values for a variety of RWUCollator attributes. Collator attributes can be overridden using mutator methods (Section 6.3). The getLocale() method returns the locale upon which a collator is based.

Once you've instantiated an RWUCollator, you can compare two strings according to the dictates of the collator's attributes using the compareTo() method:

int retval = collator.compareTo(str1, str2);

The compareTo() method returns:

-1 if str1 < str2
0 if str1 == str2
1 if str1 > str2

For example, coté compares less than côte in the English locale, but greater than côte in the French locale:

RWUConversionContext context("Latin1");

RWUString s1("coté");
RWUString s2("côte");

RWULocale en(RWCString("en"));
RWUCollator enCollator(en);                                 //1

cout << "\nEnglish locale: " << s1;
if (enCollator.compareTo(s1, s2) < 0) {                     //2
  cout << " is";
} else {
  cout << " is NOT";
} // else
cout << " less than " << s2 << "." << endl;

RWULocale fr(RWCString("fr"));
RWUCollator frCollator(fr);                                 //3

cout << "\nFrench locale: " << s1;
if (frCollator.compareTo(s1, s2) < 0) {                     //4
  cout << " is";
} else {
  cout << " is NOT";
} // else
cout << " less than " << s2 << << endl;

`//1`	Creates an *RWUCollator* based on the English locale.
`//2`	Compares the two strings.
`//3`	Creates an *RWUCollator* based on the French locale.
`//4`	Compares the two strings.

The output is:

English locale: coté is less than côte
French locale: coté is NOT less than côte

Similarly, the equals() method returns true if two strings compare equal according to the dictates of the collator's attributes; otherwise, false. Thus:

if ( collator.equals(str1, str2) ) {
   // Do something here...

}

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