PHP字符串替換str_replace()函數4種用法詳解

mixed str_replace ( mixed $search , mixed $replace , mixed $subject [, int &$count ] )
該函數返回一個字符串或者數組。該字符串或數組是將subject中全部的search都被replace替換之后的結果。
1、$search,要替換的字符串，或數組
2、$replace,被用來替換的字符串或數組
3、$subject,被查詢的字符串或數組
4、$count，可選，如果被指定，將為設置為替換的次數
5、返回值：該函數返回替換后的數組或者字符串(新生成的)

<?php
    //實例一：字符串替換字符串
    $str1 = str_replace("red","black","red green yellow pink purple");
    echo $str1."";    //輸出結果為black green yellow pink purple
?>

<?php
    //實例二：字符串替換數組鍵值
    $arr = array("blue","red","green","yellow");
    $str1 = str_replace("red","pink",$arr,$i);
    print_r($str1);
?>

<?php
    //實例三：數組替換數組，映射替換
    $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);
?>

<?php
    //實例四：如$search為數組，$replace為字符串時
    $search = array("banana","grape");
    $replace = "tomato";
    $arr = array("banana","apple","orange","grape");
    $new_arr = str_replace($search,$replace,$arr,$count);
    print_r($new_arr);
?>