Question

I have a json string where some part of it needs to be extracted and sent to a service. I am wondering if it’s possible to extract that specific part in jquery using expressions or any other approach?

the sample json I have is

{"hashcode":[], "stringMap":{":id":"50",":question":"My roof"}, ":size":"2", ":type":"java.util.HashMap", ":typeId":"123"}

and the string I want out of it is

{":id":"50",":question":"My roof"}

Thanks in advance.

Thanks for Inputs guys. I just realized that stringMap may have an arbitary name, like stringMap_0 etc.. can I still get that part out without exactly know that name?

thanks again.

Answer 1

Let’s be clear here that JSON is just Javascript Object Notation. So what you have is several objects:

{"hashcode":[], "stringMap":{":id":"50",":question":"My roof"}, ":size":"2", ":type":"java.util.HashMap", ":typeId":"123"}

Breaking this code down further, we find the following:

"hashcode":[] //an empty array named hashcode

"stringMap":{":id":"50",":question":"My roof"} //an object named stringMap with two properties, ":id" and ":question" (not sure why the : are there, this is abnormal)

":size":"2"//a string ":size" set to the string "2" (again, what's with the :?)

":type":"java.util.HashMap"//a string ":type" set to the string "java.util.HashMap"

":typeId":"123"//a string ":typeId" set to the string "123"

You can normally reference any one of these objects using “dot” notation in Javascript. The whole thing functions a lot like a Java Enum/Hashmap/ArrayList. However, because of those “:” you have throughout it is not going to work. Normally though, you could do the following (see POC here):

<script type="text/javascript">
var jsonString = '{"hashcode":[], "stringMap":{"id":"50","question":"My roof"}, "size":"2", "type":"java.util.HashMap", "typeId":"123"}';
var data = eval("(" + jsonString + ")");
alert(data.stringMap.id);
</script>

Note that in order for that code to work, I had to remove the “:” from before “id”…