JSON.parse(), $.parseJSON() Similar Function.

Passing in a malformed JSON string results in a JavaScript exception being thrown. For example, the following are all invalid JSON strings:

• "{test: 1}" (test does not have double quotes around it).
• "{'test': 1}" ('test' is using single quotes instead of double quotes).
• "'test'" ('test' is using single quotes instead of double quotes).
• ".1" (a number must start with a digit; "0.1" would be valid).
• "undefined" (undefined cannot be represented in a JSON string; null, however, can be).
• "NaN" (NaN cannot be represented in a JSON string; direct representation of Infinity is also not permitted).