PhpMyanmar.com - Php Tutorial

Throughout your PHP career you will be using strings a great deal.

Therefore having a basic understanding of PHP strings is very important

String Creation

A string can be used directly in a function or it can be stored in a variable.

In the two examples below, the same string was created twice:

First Example -- The string was stored in a variable and then echoed.

PHP Code:

<?php

$my_string="PhpMyanmar.com-Unlock your potential!";
echo $my_string;

Display:

PhpMyanmar.com - Unlock your potential!

Second Example -- The string was directly echoed.

PHP Code:

<?php

echo "PhpMyanmar.com-Unlock your potential!";

Display:

PhpMyanmar.com - Unlock your potential!

String Creation Single Quotes

We have created strings using double-quotes up to now,? but it is just as correct to create a string using single-quotes, (apostrophes).

PHP Code:

<?php

$my_string = 'PhpMyanmar.com - Unlock your potential!';
echo 'PhpMyanmar.com - Unlock your potential!';
echo $my_string;

If you want to use a single-quote within the string you have to escape the single-quote with a backslash \ . Like this: \' !

PHP Code:

<?php

echo 'PhpMyanmar.com - It\'s super';

?>

String Creation Double-Quotes

Double-quotes should be used as?the primary method for forming strings.

Double-quotes allows many special escaped characters to be used that you cannot do with a single-quote string.

See below where backslashes are used to escape a character.

PHP Code:

<?php

$newline = "A newline is \n";
$return = "A carriage return is \r";
$tab = "A tab is \t";
$dollar = "A dollar sign is \$";
$doublequote = "A double-quote is \"";

?>

Escaped characters shown above are not very useful for outputting to a web page because HTML ignore extra white space( tab, newline, and carriage return are all examples of extra 'ignorable' white space)

But when writing to a file that may be read by human eyes these escaped characters are a valuable tool!

String Creation Heredoc

PHP has a very robust string creation tool called heredoc?

It lets the programmer create multi-line strings without using quotations.

PHP Code:

<?php

$my_test_string = <<<MYTEST
PhpMyanmar.com,
Php Tutorials,
Try it.
MYTEST;

echo $my_test_string;

?>

Few very important things to follow when using heredoc.

Use <<< and some identifier that you choose to begin the heredoc. In this example we chose MYTEST as our identifier.
Repeat the identifier followed by a semicolon to end the heredoc string creation. In this example that was MYTEST;
The closing sequence MyTEST; must occur on a line by itself and cannot be indented!

Display:

PhpMyanmar.com, Php Tutorials, Try it.

Note
For more detail please see Php Manual at http://www.php.net

သင္၏ PHP သက္တမ္း တေလ်ာက္တြင္ string မ် ားကို ႀကိမ္ဖန္ မ်ားစြာ အသံုးျပဳရ ပ ါလိမ့္မည္။.

ထို႔ေၾကာင့္ string တို႔၏ အေျခခံ သေဘာတရား မ်ားကို နားလည္ ထားရန္ အလြန္ အေရးႀကီး ပါသည္။

String မ်ားဖန္တည္းျခင္း

String မ်ားကို တိုက္ရိုက္ ေသာ္၎ variable မ်ားတြင္ သိုမွီး၍ ေသာ္၎ အသံုးျပဳ ေလ့ရွိ ပါသည္။

ဆက္လက္ ေဖၚျပမည့္ ဥပမာ ႏွစ္ခု တြင္ string တခုကို ႏွစ္မ်ိဳး ပံုေဖၚ ျပထား ပါသည္။

First Example -- String ကို ဦးစြာ variable တြင္ သိုမွီး ၿပီးမွ echo လုပ္ျခင္း။

PHP Code:

<?php

$my_string="PhpMyanmar.com-Unlock your potential!";
echo $my_string;

?>

Display:

PhpMyanmar.com - Unlock your potential!

Second Example -- String တခု ကို တိုက္ရိုက္ echo လုပ္ျခင္။

PHP Code:

<?php

echo "PhpMyanmar.com-Unlock your potential!";

?>

Display:

PhpMyanmar.com - Unlock your potential!

Single Quotes သံုး၍ string ဖန္တည္းျခင္း။

အထက္တြင္ strings မ်ား ဖန္တည္းရန္ double-quotes မ်ားကိုသာ ေတာက္ ေလ်ာက္ အသံုးျပဳလာ ခဲ့ပါသည္။ သို႔ေသာ္ single-quotes, (apostrophes) သံုး၍လည္း string မ်ားကို ဖန္တည္း ႏိုင္ပါ ေသးသည္။

PHP Code:

<?php

$my_string = 'PhpMyanmar.com - Unlock your potential!';
echo 'PhpMyanmar.com - Unlock your potential!';
echo $my_string;

?>

String တခုတြင္ single-quote ကိုထည့္သြင္းေဖၚျပ လိုပါက backslash [ \ ] ခံ၍ ေဖၚျပ ႏိုင္ ပါသည္။ ဤသို႔ ေဆာင္ရြက္ သည္ကို escape လုပ္သည္ဟု ေခၚ ပါသည္။!

PHP Code:

<?php

echo 'PhpMyanmar.com - It\'s super';

?>

Double-Quotes သံုး၍ string ဖန္တည္း ျခင္း။

String မ်ားဖန္တည္း ရာတြင္ double-quotes မ်ားကို ဦးစားေပး ၍ အသံုးျပဳ သင့္ ပါသည္။

Double-quotes ကိုသံုး ျခင္းျဖင့္ single-quote ႏွင့္ မသံုးႏိုင္ေသာ characters အမ်ားအျပား ကို escape လုပ္၍ အသံုးျပဳ ႏိုင္ ပါသည္။

ေအာက္တြင္ backslash မ်ားကို သံုးၿပီး အခ်ိဳ႔ characters မ်ားကို escape လုပ္ထား ပံုမ်ား ကိုေဖၚျပ ထား ပါသညိ။

PHP Code:

<?php

$newline = "A newline is \n";
$return = "A carriage return is \r";
$tab = "A tab is \t";
$dollar = "A dollar sign is \$";
$doublequote = "A double-quote is \"";

?>

အထက္ ေဖၚျပပါ escape လုပ္ထားေသာ character မ်ားမွာ HTML မ်ားတြင္ သိတ္အသံုး မဝင္ပါ။ HTML သည္ tab, newline ႏွင့္ carriage return မ်ားကို white space မ်ားအျဖစ္ သတ္မွတ္ ၿပီး လ်စ္လ်ဴရွု ပါသည္။

သို႔ေသာ္ လူ႔မ်က္လံုး ျဖင့္ ဖတ္ႏိုင္ေသာ file မ်ားကို ေရးသာ ေသာအခါ (when writing to a file) တြင္လြန္စြာ အသံုးဝင္ ပါသည္။

Heredoc ကိုသံုး၍ string ဖန္တည္းျခင္း။

PHP တြင္ အလြန္ အသံုးဝင္ေသာ heredoc ဟုေခၚေသာ string creation tool တခုရွိ ပါသည္။

Heredoc သံုး၍ multi-line strings မ်ားကို quot မ်ား မသံုးပဲ ဖန္တည္း ႏိုင္ ပါသည္။

PHP Code:

<?php

$my_test_string = <<<MYTEST
PhpMyanmar.com,
Php Tutorials,
Try it.
MYTEST;

echo $my_test_string;

?>

Heredoc ကိုသံုးေသာ အခါ တြင္ လိုက္နာ ရမည့္ စည္းမ်ဥ္း အခ်ိဳ႔။

Heredoc ကိုသံုးရာတြင္ စာေၾကာင္းကို <<< ႏွင့္ စၿပီး identifier တစ္ခု ျဖင့္ တြဲဖက္ အသံုးျပဳ ရ ပါမည္။ ေအာက္ ေဖၚျပပါ ဥပမာ တြင္ MYTEST ကို identifier အျဖစ္ သံုးထား ပါသည္။
ေနာက္ဆံုး စာေၾကာင္းတြင္ identifier MyTEST ကို semicolon [ ; ] ျဖင့္ အဆံုး သတ္ ၿပီး ပိတ္ေရး ရပါမည္။
ေနာက္ဆံုးမွ ပိတ္ေရးသည့္ MyTEST; သည္ တေၾကာင္းတည္း သီးျခား ျဖစ္ရ ပါမည္။ Indent ခံ၍ မရပါ။ (Last identifier must occur on a line by itself and cannot be indented)

Display:

PhpMyanmar.com, Php Tutorials, Try it.

Note
For more detail please see Php Manual at http://www.php.net