Why do I use Object1.optint, and object1.optstring, during the JSON parsing process?

Today in the JSON parsing, there was a piece of code did not execute the problem, and then looked for a reason:

1, the original code is:

found that the red sentence did not execute, view the console found an exception

2, fix the bug, the correct code for

3. Summary

1, we parse the method GetString ("") is because the JSON does not exist in this value, will report an exception, resulting in the following code will not execute

2, security I generally use optstring method, this way will not report abnormal

3,object1.optint ("id") does not exist this value, return 0

Object1.optstring ("mobile") does not exist for this value and returns an empty

Why do I use Object1.optint, and object1.optstring, during the JSON parsing process?