附加2个或更多json字符串

Question

I have form where in I dynamically create json strings and append those strings in a hidden field.

for example : Imagine I have a hidden field with id as "json_hidden_field" and my dynamically created jsons will look something like below

var json_str1 = "{ "name" : "foo1" , "value" : "bar1" }"

var json_str2 = "{ "name" : "foo2" , "value" : "bar2" }"

What I am looking for is to append the string in such a way that the resulting output is

"{ "name" : "foo1" , "value" : "bar1" } , { "name" : "foo2" , "value" : "bar2" }"

And to achieve this , this is what I have written but I am kind of annoyed by the fact that I have to handle that comma in such a way

  full_json= $("#json_hidden_field").val().concat($("#json_hidden_field").val() ? "," : "" , json_str2 )


$("#json_hidden_field").val(full_json)

I need help refactoring this piece of code.

Thanks

Answer 1

var json_str1 = '{ "name" : "foo1" , "value" : "bar1" }'
var json_str2 = '{ "name" : "foo2" , "value" : "bar2" }'

full_json = [json_str1, json_str2].join(',');

Answer 2

Do this:

full_json = [json_str1, json_str2].join();

---

but if you want to keep it valid JSON, then do this:

full_json = "[" + [json_str1, json_str2].join() + "]";

---

Or better, don't create your JSON strings manually.

var json_str1 = { name : "foo1" , value : "bar1" }
var json_str2 = { name : "foo2" , value : "bar2" }

var full_json = JSON.stringify([json_str1, json_str2]);

Answer 3

You could put the json strings in an array, join them, then set this to the json hidden field val.

var json_str1 = "{ 'name' : 'foo1' , 'value' : 'bar1' }"
var json_str2 = "{ 'name' : 'foo2' , 'value' : 'bar2' }"
var full_json = [json_str1, json_str2].join(','))

So that full_json equals the string value:

{ 'name' : 'foo1' , 'value' : 'bar1' },{ 'name' : 'foo2' , 'value' : 'bar2' }

Then just:

$("#json_hidden_field").val(full_json) 

Answer 4

Further to the other suggestions to use an array, to me your question seems to be implying that you'll be building up the final almost-JSON result (the desired output that you specified isn't valid JSON) as part of several other operations, where possibly not all of those operations will occur every time. If so, I'd suggest creating an empty array to begin with:

var output = [];

Then at any point in your code where you need to add some more JSON just add to the end of the array:

output.push(json_str1);
// OR
output.push('{ "name" : "foo1" , "value" : "bar1" }');

Then finally when you actually want to submit the form containing your hidden field in your submit handler you'd .join() the array and put the resulting string into your hidden field:

$("#json_hidden_field").val(output.join(","));

As I mentioned above though, your desired output isn't valid JSON - it's almost JSON, but you'd need to add square brackets around it so that it represents an array of objects:

'[{ "name" : "foo1" , "value" : "bar1" } , { "name" : "foo2" , "value" : "bar2" }]'

...in which case you can use:

$("#json_hidden_field").val("[" + output.join(",") + "]");

Answer 5

function updateJsonValues(newJson){
var oldJson=$("#json_hidden_field").val().split(',');
oldJson.push(newJson);
$("#json_hidden_field").val(oldJson);
}

call updateJsonValues(newJson) whenever you get new Json string