php數組練習之----查詢數組中某key的鍵值相同的個數、數組的格式轉換、合並數組

$array  =  array() {

                 [0]=> array(6) {
                ["id"]=> string(1) "2"
                ["lessonid"]=> string(3) "200"
                ["userid"]=> string(4) "6038"
                ["username"]=> string(8) "jsc11101"
                ["lessontitle"]=> string(47) "Module1-Unit2 I'm From China "
                ["courseid"]=> string(1) "4"
                }

                 [1]=> array(6) {
                ["id"]=> string(1) "3"
                ["lessonid"]=> string(3) "201"
                ["userid"]=> string(4) "6038"
                ["username"]=> string(8) "jsc11101"
                ["lessontitle"]=> string(33) "Module2-Unit1 I Can Speak English"
                ["courseid"]=> string(1) "4"
                }
                 [5]=> array(6)
                   。。。。。。。。。。。。。。。。。。。。。。。。
}

相同lessonid的學習次數

$study_num = array();

foreach($array as $value){

                 $study_num[$value['lessonid']]=(empty($study_num[$value['lessonid']])?0:$study_num1[$value['lessonid']])+1; 

                                                                                  //如果$study_num[$value['lessonid']為第一次遍   歷賦值為空

}

學習次數：   $study_num[$lessionid]

轉換成以lessonid為key的數組

$lessonid_array = array();

foreach($array as $key => $value){

                 $lessonid_array[$value[lessonid]]=$value;

}

學習課文名稱：  $lessonid_array[$lessonid]['lessontitle']

合並數組

foreach($study_num as $key=>$value){

                 $lessonid_array[$key][count]=$value;

}

 輸出數組形式如下
               

$a_array  = array(){              
          lessonid號 => array(7) {
                  

                 ["id"]=> string(1) "3"
                ["lessonid"]=> string(3) "學習課文ID"
                ["userid"]=> string(4) "6038"
                ["username"]=> string(8) "jsc11101"
                ["lessontitle"]=> string(33) "學習課文名稱"
                ["courseid"]=> string(1) "4"
                ["count"]=>"學習次數"

}
}