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php 修改数据中某个元素值，其它元素值不变。

循环数组

array(8) {
 [0] => array(10) {
 ["opid"] => int(0)
 ["pid"] => int(11)
 ["price"] => string(4) "0.10"
 ["controller"] => string(4) "Live"
 ["type_mold"] => int(1)
 ["img"] => string(0) ""
 ["description"] => string(4) "1212"
 ["title"] => string(12) "测试回放"
 ["user_id"] => int(51)
 ["limit"] => string(19) "2020-01-25 15:03:14"
 }
 [1] => array(10) {
 ["opid"] => int(0)
 ["pid"] => int(10)
 ["price"] => string(4) "0.10"
 ["controller"] => string(4) "Live"
 ["type_mold"] => int(1)
 ["img"] => string(0) ""
 ["description"] => string(2) "12"
 ["title"] => string(12) "线上测试"
 ["user_id"] => int(51)
 ["limit"] => string(19) "2019-10-17 15:03:14"
 }
 [2] => array(10) {
 ["opid"] => int(0)
 ["pid"] => int(3)
 ["price"] => string(4) "1.00"
 ["controller"] => string(4) "Live"
 ["type_mold"] => int(1)
 ["img"] => string(0) ""
 ["description"] => string(4) "1212"
 ["title"] => string(21) "测试保长时直播"
 ["user_id"] => int(51)
 ["limit"] => string(19) "2019-10-17 15:03:14"
 }
 [3] => array(10) {
 ["opid"] => int(0)
 ["pid"] => int(2)
 ["price"] => string(4) "0.10"
 ["controller"] => string(5) "Video"
 ["type_mold"] => int(2)
 ["img"] => string(0) ""
 ["description"] => string(130) "最近长安刚刚公布了全新中型SUV CS85的预售价格，售价区间为14.99-17.19万元，成为长安首款轿跑SUV。"
 ["title"] => string(142) "测试点播最近长安刚刚公布了全新中型SUV CS85的预售价格，售价区间为14.99-17.19万元，成为长安首款轿跑SUV。"
 ["user_id"] => int(51)
 ["limit"] => string(19) "2019-10-17 15:03:14"
 }
 [4] => array(10) {
 ["opid"] => int(0)
 ["pid"] => int(8)
 ["price"] => string(4) "0.00"
 ["controller"] => string(4) "Shop"
 ["type_mold"] => int(4)
 ["img"] => string(0) ""
 ["description"] => string(0) ""
 ["title"] => string(3) "111"
 ["user_id"] => int(51)
 ["limit"] => string(19) "2019-10-17 15:03:14"
 }
 [5] => array(10) {
 ["opid"] => int(0)
 ["pid"] => int(61)
 ["price"] => string(4) "0.00"
 ["controller"] => string(9) "Testpaper"
 ["type_mold"] => int(3)
 ["img"] => string(45) "20190403/c378d2084ec9c3f05ceab36c00ac67a4.png"
 ["description"] => string(6) "健康"
 ["title"] => string(12) "健康管理"
 ["user_id"] => int(51)
 ["limit"] => string(19) "2022-01-14 15:03:14"
 }
 [6] => array(10) {
 ["opid"] => int(0)
 ["pid"] => int(55)
 ["price"] => string(4) "0.00"
 ["controller"] => string(9) "Testpaper"
 ["type_mold"] => int(3)
 ["img"] => string(45) "20190330/af4db555769d715ae163bfd0a3c05b.jpg"
 ["description"] => string(3) "111"
 ["title"] => string(27) "模板导入试卷测试一"
 ["user_id"] => int(51)
 ["limit"] => string(19) "2019-05-01 15:03:14"
 }
 [7] => array(10) {
 ["opid"] => int(0)
 ["pid"] => int(62)
 ["price"] => string(7) "1000.00"
 ["controller"] => string(9) "Testpaper"
 ["type_mold"] => int(3)
 ["img"] => string(45) "20190330/f1cc9c7df38108c505338a529e3d06a6.jpg"
 ["description"] => string(18) "法学概论201704"
 ["title"] => string(18) "法学概论201704"
 ["user_id"] => int(51)
 ["limit"] => string(19) "2019-07-29 15:03:14"
 }
}

方法：

foreach($pid_arr_t as $key=>$value){
 $value['opid'] = 123;
 $pid_arr_t[$key] = $value; 
 }

只有修改opid的元素值.