amt: "10.00"
email: "sam@gmail.com"
merchant_id: "sam"
mobileNo: "9874563210"
orderID: "123456"
passkey: "1234"
以上就是我要处理的JSON对象。我想检查merchant_id键是否存在。我尝试了下面的代码，但它不工作。有办法实现吗?
<script>
window.onload = function getApp()
{
var thisSession = JSON.parse('<?php echo json_encode($_POST); ?>');
//console.log(thisSession);
if (!("merchant_id" in thisSession)==0)
{
// do nothing.
}
else
{
alert("yeah");
}
}
</script>
当前回答
函数检查未定义和空对象
function elementCheck(objarray, callback) {
var list_undefined = "";
async.forEachOf(objarray, function (item, key, next_key) {
console.log("item----->", item);
console.log("key----->", key);
if (item == undefined || item == '') {
list_undefined = list_undefined + "" + key + "!! ";
next_key(null);
} else {
next_key(null);
}
}, function (next_key) {
callback(list_undefined);
})
}
这是一个简单的方法来检查对象发送是否包含未定义或空
var objarray={
"passenger_id":"59b64a2ad328b62e41f9050d",
"started_ride":"1",
"bus_id":"59b8f920e6f7b87b855393ca",
"route_id":"59b1333c36a6c342e132f5d5",
"start_location":"",
"stop_location":""
}
elementCheck(objarray,function(list){
console.log("list");
)
其他回答
试试这个,
if(thisSession.hasOwnProperty('merchant_id')){
}
JS对象thisSession应该像这样
{
amt: "10.00",
email: "sam@gmail.com",
merchant_id: "sam",
mobileNo: "9874563210",
orderID: "123456",
passkey: "1234"
}
你可以在这里找到细节
你可以试试if(typeof object !== 'undefined')
你可以这样做:
if("merchant_id" in thisSession){ /** will return true if exist */
console.log('Exist!');
}
or
if(thisSession["merchant_id"]){ /** will return its value if exist */
console.log('Exist!');
}
函数检查未定义和空对象
function elementCheck(objarray, callback) {
var list_undefined = "";
async.forEachOf(objarray, function (item, key, next_key) {
console.log("item----->", item);
console.log("key----->", key);
if (item == undefined || item == '') {
list_undefined = list_undefined + "" + key + "!! ";
next_key(null);
} else {
next_key(null);
}
}, function (next_key) {
callback(list_undefined);
})
}
这是一个简单的方法来检查对象发送是否包含未定义或空
var objarray={
"passenger_id":"59b64a2ad328b62e41f9050d",
"started_ride":"1",
"bus_id":"59b8f920e6f7b87b855393ca",
"route_id":"59b1333c36a6c342e132f5d5",
"start_location":"",
"stop_location":""
}
elementCheck(objarray,function(list){
console.log("list");
)
类型检查也适用:
if(typeof Obj.property == "undefined"){
// Assign value to the property here
Obj.property = someValue;
}
