PHP基础2

1. sprintf  Replace the percent (%) sign by a variable passed as an argument:

http://www.w3schools.com/php/func_string_sprintf.asp

<?php

$number = 9;

$str = "Beijing";

$txt = sprintf("There are %u million bicycles in %s.",$number,$str);

echo $txt;

?>

 2. global variable

using global variable inside function

<?php

function echo_ip(){

    global $user_ip;

    $string = "your ip addr is ".$user_ip;

    echo $string;

}

echo_ip();

?>

 3. print_r

Prints human-readable information about a variable

 

<?php

$string = 'this is a example string';

$string_word_count = str_word_count($string,1);

print_r($string_word_count);

?>

 4. str_word_count

　　second parameter

　　　　0: the number of words

　　　　1: put words in array,

　　　　2. put words in array, key is the position of the words in the string

<?php

$string = 'this is a example string';

$string_word_count = str_word_count($string,1);

print_r($string_word_count);

?>

 the function ignore other character, to not ignore certain character

<?php

$string = 'this is a example string , $ &';

$string_word_count = str_word_count($string,1,',&');

print_r($string_word_count);

?>

 5. string concatenation

dot

<?php

$string1 ='apple '.'banana';

$string2 =' pig';

echo $string1.$string2;

?>