Home >Backend Development >PHP Tutorial >PHP array exercise--query the number of the same key value of a certain key in the array, format conversion of the array, and merge arrays_PHP tutorial
$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的学习次数
$study_num = array();
foreach($array as $value){
$study_num[$value['lessonid']]=(empty($study_num[$value['lessonid']])?0:$study_num1[$value['lessonid']])+1;
//如果$study_num[$value['lessonid']为第一次遍 历赋值为空
}
学习次数: $study_num[$lessionid]
转换成以lessonid为key的数组
$lessonid_array = array();
foreach($array as $key => $value){
$lessonid_array[$value[lessonid]]=$value;
}
学习课文名称: $lessonid_array[$lessonid]['lessontitle']
合并数组
foreach($study_num as $key=>$value){
$lessonid_array[$key][count]=$value;
}
输出数组形式如下
$a_array = array(){
lessonid号 => array(7) {
Since
["lessonid"]=> string(3) "Learning text ID"
["userid"]=> string(4) "6038"
["username"]=> string(8) "jsc11101"
since through ["lessontitle"]=>
["courseid"]=> string(1) "4"
["count"]=>"Number of learning times"
}
Excerpted from xiaxia0083’s column
http://www.bkjia.com/PHPjc/478290.html