Say I have this JSON:

[

{

"ID": "1",

"title": "Title 1",

},

{

"ID": "2",

"title": "Title 2",

}

]

How would I return the set of key names that recur for each record? In this case, ID, title.

I tried:

$.getJSON('testing.json', function(data) {

var items = [];

$.each(data, function(key, val) {

items.push(key +', ');

});

$('

html: items.join('')

}).appendTo('#content');

});

without success.

This is a JSON "database", and every "record" has the same keys. I just want a script that will tell me what the keys are, not test whether or not they occur in every entry.

解决方案

This will give you an array of all the string properties that match across an array of objects. Is that what you are looking for?

$.getJSON('testing.json', function(data) {

var propertiesThatExistInAll = getPropertiesThatExistInAll(data);

});

var getPropertiesThatExistInAll = function(arr) {

var properties = $.map(data[0], function (prop, value) {

return prop;

});

var propertiesThatExistInAll = [];

$.each(properties, function (index, property) {

var keyExistsInAll = true;

// skip the first one since we know it has all the properties

for (var i = 1, len = data.length; i < len; i++) {

if (!data[i].hasOwnProperty(property)) {

keyExistsInAll = false;

break;

}

}

if (keyExistsInAll) {

propertiesThatExistInAll.push(property);

}

});

return propertiesThatExistInAll;

};