Message Formatting Examples

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MessageFormat Class

ICU's MessageFormat class can be used to format messages in a locale-independent manner to localize the user interface (UI) strings.

C++

/* The strings below can be isolated into a resource

bundle

* and retrieved dynamically

*/

#define LANGUAGE_NAMES "{0}<{1}languages {2}>\n"

#define LANG_ATTRIB "{0}<language id=\"{1}\" >{2}</language>\n"

#define MONTH_NAMES "{0}<monthNames>\n"

#define END_MONTH_NAMES "{0}</monthNames>\n"

#define MONTH "{0}<month id=\"{1}\">{2}</month>\n"

#define MONTH_ABBR "{0}<monthAbbr>\n"

#define END_MONTH_ABBR "{0}</monthAbbr>\n"

UnicodeString CXMLGenerator::formatString(UnicodeString& str,UnicodeString&

argument){

Formattable args[] ={ argument};

UnicodeString result;

MessageFormat format(str,mError);

FieldPosition fpos=0;

format.format(args,1, result,fpos,mError);

if(U_FAILURE(mError)) {

return UnicodeString("Illegal argument");

}

return result;

}

void CXMLGenerator::writeLanguage(UnicodeString& xmlString){

UnicodeString *itemTags, *items;

char* key="Languages";

int32_t numItems;

if(U_FAILURE(mError)) {

return;

}

mRBundle.getTaggedArray(key,itemTags, items, numItems, mError);

if(mError!=U_USING_DEFAULT_ERROR && U_SUCCESS(mError) &&

mError!=U_ERROR_INFO_START){

Formattable args[]={indentOffset,"",""};

xmlString= formatString(UnicodeString(LANGUAGE_NAMES),args,3);

indentOffset.append("\t");

for(int32_t i=0;i<numItems;i++){

args[0] = indentOffset;

args[1] =itemTags[i] ;

args[2] = items[i] ;

xmlString.append(formatString(UnicodeString(LANG_ATTRIB),args,3));

}

chopIndent();

args[0]=indentOffset;

args[1] =(UnicodeString(XML_END_SLASH));

args[2] = "";

xmlString.append(formatString(UnicodeString(LANGUAGE_NAMES),args,3));

return;

}

mError=U_ZERO_ERROR;

xmlString.remove();

}

void CXMLGenerator::writeMonthNames(UnicodeString& xmlString){

int32_t lNum;

const UnicodeString* longMonths=

mRBundle.getStringArray("MonthNames",lNum,mError);

if(mError!=U_USING_DEFAULT_ERROR && mError!=U_ERROR_INFO_START && mError !=

U_MISSING_RESOURCE_ERROR){

xmlString.append(formatString(UnicodeString(MONTH_NAMES),indentOffset));

indentOffset.append("\t");

for(int i=0;i<lNum;i++){

char c;

itoa(i+1,&c,10);

Formattable args[]={indentOffset,UnicodeString(&c),longMonths[i]};

xmlString.append(formatString(UnicodeString(MONTH),args,3));

}

chopIndent();

xmlString.append(formatString(UnicodeString(END_MONTH_NAMES),indentOffset));

mError=U_ZERO_ERROR;

return;

}

xmlString.remove();

mError= U_ZERO_ERROR;

}

C

void msgSample1(){

UChar *result, *tzID, *str;

UChar pattern[100];

int32_t resultLengthOut, resultlength;

UCalendar *cal;

UDate d1;

UErrorCode status = U_ZERO_ERROR;

str=(UChar*)malloc(sizeof(UChar) * (strlen("disturbance in force") +1));

u_uastrcpy(str, "disturbance in force");

tzID=(UChar*)malloc(sizeof(UChar) * 4);

u_uastrcpy(tzID, "PST");

cal=ucal_open(tzID, u_strlen(tzID), "en_US", UCAL_TRADITIONAL, &status);

ucal_setDateTime(cal, 1999, UCAL_MARCH, 18, 0, 0, 0, &status);

d1=ucal_getMillis(cal, &status);

u_uastrcpy(pattern, "On {0, date, long}, there was a {1} on planet

{2,number,integer}");

resultlength=0;

resultLengthOut=u_formatMessage( "en_US", pattern, u_strlen(pattern),

NULL,

resultlength, &status, d1, str, 7);

if(status==U_BUFFER_OVERFLOW_ERROR){

status=U_ZERO_ERROR;

resultlength=resultLengthOut+1;

result=(UChar*)realloc(result, sizeof(UChar) * resultlength);

u_formatMessage( "en_US", pattern, u_strlen(pattern), result,

resultlength, &status, d1, str, 7);

}

printf("%s\n",austrdup(result) ); //austrdup( a function used to convert

UChar* to char*)

free(tzID);

free(str);

free(result);

}

char *austrdup(const UChar* unichars)

{

int length;

char *newString;

length = u_strlen ( unichars );

newString = (char*)malloc ( sizeof( char ) * 4 * ( length + 1 ) );

if ( newString == NULL )

return NULL;

u_austrcpy ( newString, unichars );

return newString;

}

This is a more practical sample which retrieves data from a resource bundle

and

feeds the data

to u_formatMessage to produce a formatted string

void msgSample3(){

char* key="Languages";

int32_t numItems;

/* This constant string can also be in the resouce bundle and retrieved at

the time

* of formatting

* eg:

* UResouceBundle* myResB = ures_open("myResources",currentLocale,&err);

* UChar* Lang_Attrib = ures_getString(myResb,"LANG_ATTRIB",&err);

*/

UChar* LANG_ATTRIB =(UChar*) "{0}<language id=\"{1}\"

>{2}</language>\n";

UChar *result;

UResourceBundle* pResB,*pDeltaResB=NULL;

UErrorCode err=U_ZERO_ERROR;

UChar* indentOffset = (UChar*)"\t\t\t";

pResB = ures_open("","en",&err);

if(U_FAILURE(err)) {

return;

}

ures_getByKey(pResB, key, pDeltaResB, &err);

if(U_SUCCESS(err)) {

const UChar *value = 0;

const char *key = 0;

int32_t len = 0;

int16_t indexR = -1;

int32_t resultLength=0,resultLengthOut=0;

numItems = ures_getSize(pDeltaResB);

for(;numItems-->0;){

key= ures_getKey(pDeltaResB);

value = ures_get(pDeltaResB,key,&err);

resultLength=0;

resultLengthOut=u_formatMessage( "en_US", LANG_ATTRIB,

u_strlen(LANG_ATTRIB),

NULL, resultLength, &err,

indentOffset, value, key);

if(err==U_BUFFER_OVERFLOW_ERROR){

err=U_ZERO_ERROR;

resultLength=resultLengthOut+1;

result=(UChar*)realloc(result, sizeof(UChar) * resultLength);

u_formatMessage("en_US",LANG_ATTRIB,u_strlen(LANG_ATTRIB),

result,resultLength,&err,indentOffset,

value,key);

printf("%s\n", austrdup(result) );

}

return;

}

err=U_ZERO_ERROR;

}

Java

import com.ibm.icu.text.*;

import java.util.Date;

import java.text.FieldPosition;

public class TestMessageFormat{

public void runTest() {

String format = "At {1,time,::jmm} on {1,date,::dMMMM}, there was {2} on planet {3,number,integer}.";

MessageFormat mf = new MessageFormat(format);

Object objectsToFormat[] = { new Date(System.currentTimeMillis()), new Date(System.currentTimeMillis()), "a Disturbance in the Force", new Integer(5)};

FieldPosition fp = new FieldPosition(1);

StringBuffer sb = new StringBuffer();

try{

sb = mf.format(objectsToFormat, sb, fp);

System.out.println(sb.toString());

}catch(IllegalArgumentException e){

System.out.println("Exception during formating of type :" +e);

}

public static void main(String args[]){

try{

new TestMessageFormat().runTest();

}catch(Exception e){

System.out.println("Exception of type: "+e);

}

ChoiceFormat Class

Important: The following documentation is outdated. ChoiceFormat is probably not what you need. Please use MessageFormat with plural arguments for proper plural selection, and select arguments for simple selection among a fixed set of choices!

ICU's ChoiceFormat class provides more flexibility than the printf() and scanf() style functions for formatting UI strings. This interface can be useful if you would like a message to change according to the number of items you are displaying. Note: Some Asian languages do not have plural words or phrases.

C++

void msgSample1(){

UChar *result, *tzID, *str;

UChar pattern[100];

int32_t resultLengthOut, resultlength;

UCalendar *cal;

UDate d1;

UErrorCode status = U_ZERO_ERROR;

str=(UChar*)malloc(sizeof(UChar) * (strlen("disturbance in force") +1));

u_uastrcpy(str, "disturbance in force");

tzID=(UChar*)malloc(sizeof(UChar) * 4);

u_uastrcpy(tzID, "PST");

cal=ucal_open(tzID, u_strlen(tzID), "en_US", UCAL_TRADITIONAL, &status);

ucal_setDateTime(cal, 1999, UCAL_MARCH, 18, 0, 0, 0, &status);

d1=ucal_getMillis(cal, &status);

u_uastrcpy(pattern, "On {0, date, long}, there was a {1} on planet

{2,number,integer}");

resultlength=0;

resultLengthOut=u_formatMessage( "en_US", pattern, u_strlen(pattern),

NULL,

resultlength, &status, d1, str, 7);

if(status==U_BUFFER_OVERFLOW_ERROR){

status=U_ZERO_ERROR;

resultlength=resultLengthOut+1;

result=(UChar*)realloc(result, sizeof(UChar) * resultlength);

u_formatMessage( "en_US", pattern, u_strlen(pattern), result,

resultlength, &status, d1, str, 7);

}

printf("%s\n",austrdup(result) ); //austrdup( a function used to convert

UChar* to char*)

free(tzID);

free(str);

double filelimits[] = {0,1,2};

UErrorCode err;

UnicodeString filepart[] = {"are no files","is one file","are {2} files"};

ChoiceFormat fileform(filelimits, filepart,err);

Format testFormats[] = {fileform, null, NumberFormat.getInstance()};

MessageFormat pattform("There {0} on {1}",err);

pattform.setFormats(testFormats);

Formattable testArgs[] = {null, "ADisk", null};

for (int i = 0; i < 4; ++i) {

testArgs[0] = i;

testArgs[2] = testArgs[0];

FieldPosition fpos=0;

format.format(args,1, result,fpos,mError);

UnicodeString result = pattform.format(testArgs);

}

C

void msgSample2(){

UChar* str;

UErrorCode status = U_ZERO_ERROR;

UChar *result;

UChar pattern[100];

int32_t resultlength,resultLengthOut, i;

double testArgs[3]= { 100.0, 1.0, 0.0};

str=(UChar*)malloc(sizeof(UChar) * 10);

u_uastrcpy(str, "MyDisk");

u_uastrcpy(pattern, "The disk {1} contains {0,choice,0#no files|1#one

file|1<{0,number,integer} files}");

for(i=0; i<3; i++){

resultlength=0;

resultLengthOut=u_formatMessage( "en_US", pattern, u_strlen(pattern),

NULL, resultlength, &status, testArgs[i], str);

if(status==U_BUFFER_OVERFLOW_ERROR){

status=U_ZERO_ERROR;

resultlength=resultLengthOut+1;

result=(UChar*)malloc(sizeof(UChar) * resultlength);

u_formatMessage( "en_US", pattern, u_strlen(pattern), result,

resultlength, &status, testArgs[i], str);

}

printf("%s\n", austrdup(result) ); //austrdup( a function used to

convert

UChar* to char*)

free(result);

}

Java

import java.text.ChoiceFormat;

import com.ibm.icu.text.*;

import java.text.Format;

public class TestChoiceFormat{

public void run(){

double[] filelimits = {0,1,2};

String[] filepart = {"are no files","is one file","are {2} files"};

ChoiceFormat fileform = new ChoiceFormat(filelimits,filepart);

Format[] testFormats = {fileform,null,NumberFormat.getInstance()};

MessageFormat pattform = new MessageFormat("There {0} on {1}");

Object[] testArgs = {null,"ADisk",null};

for(int i=0;i<4;++i) {

testArgs[0] = new Integer(i);

testArgs[2] = testArgs[0];

System.out.println(pattform.format(testArgs));

}

public static void main(String args[]){

new TestChoiceFormat().run();

}