如何使用jQuery循环遍历JSON文件

Question

I am trying loop through the following JSON file below:

 {
     "statements": [{
         "subject": "A"
     }, {
         "predicate": "B"
     }, {
         "object": "C"
     }, {
         "subject": "D"
     }, {
         "predicate": "E"
     }, {
         "object": "F"
     }]
 }

As you can see, there are two subjects, two predicates and two objects. I would like to get, for instance, the value "predicate":"E" . How can I do this using jQuery or D3 Javascript library. My code below retrieves the first subject "subject":"A" .

$.each(data.statements[0], function(i, v){
console.log(v.uriString);
});

or in D3 (I do not know how to do this in D3):

d3.json("folder/sample.json", function(error, graph) 
{  // Code is here for getting data from JSON file }

Could anyone please help me loop through the JSON file above and retrieve some particular data either with jQuery or D3 Javascript. Thank you for your help in advance.

Answer 1

The reason why your code returns the first item is beacuse you selected it with data.statments[0] and afterwards loop over that one item.

With jQuery you can use the grep-method like this:

var arrayWithItem = jQuery.grep(data.statements, function( obj ) {
  return obj.predicate == "E";
});

You can read more about the grep-method here

With D3js I'm not sure, I guess you have to loop through it with an if-statement.

Answer 2

Try this:

$(data.statements).each(function (i) {
    var d = data.statements[i];
    $.each(d, function (k, v) { //get key and value of object
        $("body").append("<p>"+k + ":" + v+"</p>");
    });
})

Fiddle here.