---
layout: default
title: Date and Time Formatting Examples
nav_order: 1
grand_parent: Formatting
parent: Formatting Dates and Times
---
# Date and Time Formatting Examples
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## Contents
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1. TOC
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---
## Format
The ICU DateFormat interface enables you to format a date in milliseconds into a
string representation of the date. Also, the interface enables you to parse the
string back to the internal date representation in milliseconds.
### C++
```cpp
DateFormat* df = DateFormat::createDateInstance();
UnicodeString myString;
UDate myDateArr[] = { 0.0, 100000000.0, 2000000000.0 };
for (int32_t i = 0; i < 3; ++i) {
myString.remove();
cout << df->format( myDateArr[i], myString ) << endl;
}
```
### C
```c
/* 1st example: format the dates in millis 100000000 and 2000000000 */
UErrorCode status=U_ZERO_ERROR;
int32_t i, myStrlen=0;
UChar* myString;
UDate myDateArr[] = { 0.0, 100000000.0, 2000000000.0 }; // test values
UDateFormat* df = udat_open(UCAL_DEFAULT, UCAL_DEFAULT, NULL, "GMT", &status);
for (i = 0; i < 3; ++i) {
myStrlen = udat_format(df, myDateArr[i], NULL, myStrlen, NULL, &status);
if(status==U_BUFFER_OVERFLOW_ERROR){
status=U_ZERO_ERROR;
myString=(UChar*)malloc(sizeof(UChar) * (myStrlen+1) );
udat_format(df, myDateArr[i], myString, myStrlen+1, NULL, &status);
printf("%s\n", austrdup(myString) );
/* austrdup( a function used to convert UChar* to char*) */
free(myString);
}
}
```
## Parse
To parse a date for a different locale, specify it in the locale call. This call
creates a formatting object.
### C++
```cpp
DateFormat* df = DateFormat::createDateInstance
( DateFormat::SHORT, Locale::getFrance());
```
### C
```c
/* 2nd example: parse a date with short French date/time formatter */
UDateFormat* df = udat_open(UDAT_SHORT, UDAT_SHORT, "fr_FR", "GMT", &status);
UErrorCode status = U_ZERO_ERROR;
int32_t parsepos=0;
UDate myDate = udat_parse(df, myString, u_strlen(myString), &parsepos,
&status);
```
### Java
```java
import java.text.FieldPosition;
import java.text.ParseException;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;
import com.ibm.icu.text.DateFormat;
public class TestDateTimeFormat {
public void run() {
// Formatting Dates
DateFormat dfUS = DateFormat.getDateInstance(DateFormat.FULL, Locale.US);
DateFormat dfFrance = DateFormat.getDateInstance(DateFormat.FULL, Locale.FRANCE);
StringBuffer sb = new StringBuffer();
Calendar c = Calendar.getInstance();
Date d = c.getTime();
sb = dfUS.format(d, sb, new FieldPosition(0));
System.out.println(sb.toString());
StringBuffer sbf = new StringBuffer();
sbf = dfFrance.format(d, sbf, new FieldPosition(0));
System.out.println(sbf.toString());
StringBuffer sbg = new StringBuffer();
DateFormat dfg = DateFormat.getDateTimeInstance(DateFormat.FULL, DateFormat.SHORT);
FieldPosition pos = new FieldPosition(DateFormat.MINUTE_FIELD);
sbg = dfg.format(d, sbg, pos);
System.out.println(sbg.toString());
System.out.println(sbg.toString().substring(pos.getBeginIndex(), pos.getEndIndex()));
// Parsing Dates
String dateString_US = "Thursday, February 7, 2008";
String dateString_FRANCE = "jeudi 7 février 2008";
try {
Date parsedDate_US = dfUS.parse(dateString_US);
Date parsedDate_FRANCE = dfFrance.parse(dateString_FRANCE);
System.out.println(parsedDate_US.toString());
System.out.println(parsedDate_FRANCE.toString());
} catch (ParseException pe) {
System.out.println("Exception while parsing :" + pe);
}
}
public static void main(String args[]) {
new TestDateTimeFormat().run();
}
}
```
## Getting Specific Date Fields
To get specific fields of a date, you can use the FieldPosition function for C++
or UFieldPosition function for C.
### C++
```cpp
UErrorCode status = U_ZERO_ERROR;
FieldPosition pos(DateFormat::YEAR_FIELD)
UDate myDate = Calendar::getNow();
UnicodeString str;
DateFormat* df = DateFormat::createDateInstance
( DateFormat::LONG, Locale::getFrance());
df->format(myDate, str, pos, status);
cout << pos.getBeginIndex() << "," << pos. getEndIndex() << endl;
```
### C
```c
UErrorCode status = U_ZERO_ERROR;
UFieldPosition pos;
UChar *myString;
int32_t myStrlen = 0;
char buffer[1024];
pos.field = 1; /* Same as the DateFormat::EField enum */
UDateFormat* dfmt = udat_open(UCAL_DEFAULT, UCAL_DEFAULT, NULL, "PST",
&status);
myStrlen = udat_format(dfmt, myDate, NULL, myStrlen, &pos, &status);
if (status==U_BUFFER_OVERFLOW_ERROR){
status=U_ZERO_ERROR;
myString=(UChar*)malloc(sizeof(UChar) * (myStrlen+1) );
udat_format(dfmt, myDate, myString, myStrlen+1, &pos, &status);
}
printf("date format: %s\n", u_austrcpy(buffer, myString));
buffer[pos.endIndex] = 0; // NULL terminate the string.
printf("UFieldPosition position equals %s\n", &buffer[pos.beginIndex]);
```
## DateTimePatternGenerator
This class lets you get a different variety of patterns, such as month+day. The
following illustrates this in Java, C++ and C.
### Java
```java
// set up the generator
DateTimePatternGenerator generator
= DateTimePatternGenerator.getInstance(locale);
// get a pattern for an abbreviated month and day
final String pattern = generator.getBestPattern("MMMd");
SimpleDateFormat formatter = new SimpleDateFormat(pattern, locale);
// use it to format (or parse)
String formatted = formatter.format(new Date());
// for French, the result is "13 sept."
```
### C++
```cpp
// set up the generator
status = U_ZERO_ERROR;
DateTimePatternGenerator *generator = DateTimePatternGenerator::createInstance( locale, status);
if (U_FAILURE(status)) {
return;
}
// get a pattern for an abbreviated month and day
UnicodeString pattern = generator->getBestPattern(UnicodeString("MMMd"), status);
SimpleDateFormat *formatter = new SimpleDateFormat(pattern, locale, status);
// use it to format (or parse)
UnicodeString formatted;
formatted = formatter->format(Calendar::getNow(), formatted, status);
// for French, the result is "13 sept."
```
### C
```c
const UChar skeleton[]= {'M', 'M', 'M', 'd', 0};
status=U_ZERO_ERROR;
generator=udatpg_open(locale, &status);
if(U_FAILURE(status)) {
return;
}
/* get a pattern for an abbreviated month and day */
length = udatpg_getBestPattern(generator, skeleton, 4,
pattern, patternCapacity, &status);
formatter = udat_open(UDAT_IGNORE, UDAT_DEFAULT, locale, NULL, -1,
pattern, length, &status);
/* use it to format (or parse) */
formattedCapacity = (int32_t)(sizeof(formatted)/sizeof((formatted)[0]));
resultLen=udat_format(formatter, ucal_getNow(), formatted, formattedCapacity,
NULL, &status);
/* for French, the result is "13 sept." */
```
## Changing the TimeZone Formatting Style
It also contains some helper functions for parsing patterns. Here's an example
of replacing the kind of timezone used in a pattern.
### Java
```cpp
/**
* Replace the zone string with a different type, eg v's for z's, etc.
* Called with a pattern, such as one gotten from
*
* String pattern = ((SimpleDateFormat)
* DateFormat.getTimeInstance(style, locale)).toPattern();
*
* @param pattern original pattern to change, such as "HH:mm zzzz"
* @param newZone Must be: z, zzzz, Z, ZZZZ, v, vvvv, V, or VVVV
* @return
*/
public String replaceZoneString(String pattern, String newZone) {
DateTimePatternGenerator.FormatParser formatParser =
new DateTimePatternGenerator.FormatParser();
final List itemList = formatParser.set(pattern).getItems();
boolean found = false;
for (int i = 0; i < itemList.size(); ++i) {
Object item = itemList.get(i);
if (item instanceof VariableField) {
// the first character of the variable field determines the type,
// according to CLDR.
String variableField = item.toString();
switch (variableField.charAt(0)) {
case 'z': case 'Z': case 'v': case 'V':
if (!variableField.equals(newZone)) {
found = true;
itemList.set(i, new VariableField(newZone));
}
break;
}
}
}
return found ? formatParser.toString() : pattern;
}
```