查詢字元串中子字元串出現位置

JS中 indexOf()方法可返回某個指定的字元串值在字元串中首次出現的位置。運用第二個參數，迴圈調用就能獲取到子串出現的所有位置

 1   /**
 2    * 查詢字元串中子字元串出現位置
 3    * @param str
 4    * @param substr
 5    * @return {Array}
 6    */
 7   function search_substr_pos(str, substr) {
 8     var _search_pos = str.indexOf(substr), _arr_positions = [];
 9     while (_search_pos > -1) {
10       _arr_positions.push(_search_pos);
11       _search_pos = str.indexOf(substr, _search_pos + 1);
12     }
13     return _arr_positions;
14   }
15 
16   var str = "look at me,is there anything can prove that I am a good guy ?";
17   var $_pos_substr = search_substr_pos(str, 'e');//子串位置
18   var $_times_substr = $_pos_substr.length;//出現次數
19 
20   console.log($_pos_substr);    //  [ 9, 16, 18, 37 ]
21   console.log($_times_substr);  //  4

同理，PHP中使用strpos()

 1 /**
 2  * 查詢字元串中子字元串出現位置
 3  * @param $str
 4  * @param $substr
 5  * @return array
 6  */
 7 function search_substr_pos($str, $substr)
 8 {
 9   $_search_pos = strpos($str, $substr);
10   $_arr_positions = array();
11   while ($_search_pos > -1) {
12     $_arr_positions[] = $_search_pos;
13     $_search_pos = strpos($str, $substr, $_search_pos + 1);
14   }
15   return $_arr_positions;
16 }
17 
18 $str = "look at me,is there anything can prove that I am a good guy ?";
19 $_pos_substr = search_substr_pos($str, 'e');//子串位置
20 $_times_substr = count($_pos_substr);//出現次數
21 
22 print_r($_pos_substr);    //  Array ( [0] => 9 [1] => 16 [2] => 18 [3] => 37 )
23 print_r($_times_substr);  //  4