编辑代码

<?php 
//JSRUN引擎2.0，支持多达30种语言在线运行，全仿真在线交互输入输出。 
$milliseconds = 1571995483916;
$salt = 'e0u6fnlag06lc3pl';
$postData = [
    'payAmount' => 100,
    "adId" => 101097648,
    "appType" => 1,
    "clientIp" => "127.0.0.1",
    "dataType" => 1,
    "ascribeType" => 1,
    "channel" => 1,
    "imei" => "XJMyaLt8fDlv4a9b8/0RNQ==",//ouId二选一
    "type" => 1,
    "pkg" => "com.oppo.test",
    "mac" => "TEViR6jSgD/lECBl3Ah70eNy2gUQrQlekHkWqEGkZsU=",
    "timestamp" => $milliseconds
];

$jsonPostData = json_encode($postData);
 var_dump($jsonPostData);
 
$jsonPostData = "'". substr($jsonPostData, 0). "'";
var_dump($jsonPostData);

$jsonPostData = '{"payAmount":100,"adId":101097648,"appType":1,"clientIp":"127.0.0.1","dataType":1,"ascribeType":1,"channel":1,"imei":"XJMyaLt8fDlv4a9b8/0RNQ==","type":1,"pkg":"com.oppo.test","mac":"TEViR6jSgD/lECBl3Ah70eNy2gUQrQlekHkWqEGkZsU=","timestamp":1571995483916}';
var_dump($jsonPostData);


$contents = $jsonPostData.$milliseconds.$salt;
var_dump($contents);

//摘要
$signature = md5($contents);
var_dump($signature);
$lowerSign = strtolower($signature);
echo $lowerSign;