PHP—str_replace()替换函数的使用

一、str_replace()函数

1、定义和用法

str_replace() 函数替换字符串中的一些字符（区分大小写）。
　　注释：该函数是区分大小写的。请使用 str_ireplace() 函数执行不区分大小写的搜索。
　　注释：该函数是二进制安全的。

2、语法

str_replace(find,replace,string,count)
参数
　　find 　　　必需。规定要查找的值。
　　replace 　必需。规定替换 find 中的值的值。
　　string 　　必需。规定被搜索的字符串。
　　count 　　可选。一个变量，对替换数进行计数。

3、实例

实例01

<?php// 赋值: <body text='black'>$bodytag = str_replace("%body%", "black", "<body text='%body%'>");// 赋值: Hll Wrld f PHP$vowels = array("a", "e", "i", "o", "u", "A", "E", "I", "O", "U");$onlyconsonants = str_replace($vowels, "", "Hello World of PHP");// 赋值: You should eat pizza, beer, and ice cream every day$phrase  = "You should eat fruits, vegetables, and fiber every day.";$healthy = array("fruits", "vegetables", "fiber");$yummy   = array("pizza", "beer", "ice cream");$newphrase = str_replace($healthy, $yummy, $phrase);//赋值：Array ( [0] => B [1] => [2] => ! )$find = array("Hello","world");$replace = array("B");$arr = array("Hello","world","!");print_r(str_replace($find,$replace,$arr));// 赋值: 2$str = str_replace("ll", "", "good golly miss molly!", $count);echo $count;?>

实例02

<?php// 替换顺序$str     = "Line 1\nLine 2\rLine 3\r\nLine 4\n";$order   = array("\r\n", "\n", "\r");$replace = '<br />';// 首先替换 \r\n 字符，因此它们不会被两次转换$newstr = str_replace($order, $replace, $str);echo $newstr;?>

效果：
　　Line 1
　　Line 2
　　Line 3
　　Line 4

实例03

<?php// 输出 F ，因为 A 被 B 替换，B 又被 C 替换，以此类推...// 由于从左到右依次替换，最终 E 被 F 替换$search  = array('A', 'B', 'C', 'D', 'E');$replace = array('B', 'C', 'D', 'E', 'F');$subject = 'A';echo str_replace($search, $replace, $subject);
?>

效果：
　　F

实例04

<?php// 输出: apearpearle pear// 由于上面提到的原因$letters = array('a', 'p');$fruit   = array('apple', 'pear');$text    = 'a p';$output  = str_replace($letters, $fruit, $text);echo $output;
?>

效果：
　　apearpearle pear

实例05

<?php//实例一：字符串替换字符串$str1 = str_replace("red","black","red green yellow pink purple");echo $str1."";  //输出结果为black green yellow pink purple//实例二：字符串替换数组键值$arr = array("blue","red","green","yellow");$str1 = str_replace("red","pink",$arr,$i);print_r($str1);//实例三：数组替换数组，映射替换$arr1 = array("banana","orange");$arr2 = array("pitaya","tomato");$con_arr = array("apple","orange","banana","grape");$con_rep = str_replace($arr1,$arr2,$con_arr,$count);print_r($con_rep);//实例四：如$search为数组，$replace为字符串时$search = array("banana","grape");$replace = "tomato";$arr = array("banana","apple","orange","grape");$new_arr = str_replace($search,$replace,$arr,$count);print_r($new_arr);
?>

效果：
　　black green yellow pink purple
　　Array ( [0] => blue [1] => pink [2] => green [3] => yellow )
　　Array ( [0] => apple [1] => tomato [2] => pitaya [3] => grape )
　　Array ( [0] => tomato [1] => apple [2] => orange [3] => tomato )