JavaScript-Questions about cross-domain access to data

When reading your own server data, the following

External data cannot be obtained, plus
Header (' Content-type:application:json;charset=utf8 ');
Header (' access-control-allow-origin:* ');
Header (' Access-control-allow-methods:post ');
Header (' Access-control-allow-headers:x-requested-with,content-type ');
After

Why do you receive different results, and the following results also belong to JSON?

Reply content:

When reading your own server data, the following

External data cannot be obtained, plus
Header (' Content-type:application:json;charset=utf8 ');
Header (' access-control-allow-origin:* ');
Header (' Access-control-allow-methods:post ');
Header (' Access-control-allow-headers:x-requested-with,content-type ');
After

Why do you receive different results, and the following results also belong to JSON?

JSONP for data acquisition across domains

Figure 2 writes clearly is an array containing two elements, and the data in Figure 1 and Figure 2 are passed JSON.strigify() and JSON.parse() can be converted to each other.

.. A cross-domain requires a specialized interface, not a random data return interface.
Requires Jsonp,script and other labels to be completed. They expect the return to be a function. There are parameters, not simple data ...
Among the family ...

Of course, the JSON format can be an array or a string, or it can be an object.

JSON.parse('true');JSON.parse('false');JSON.parse('1');JSON.parse('0');JSON.parse('"hello"');JSON.parse('""');JSON.parse('[]');JSON.parse('{}');

As long as the theory that can be correctly transformed by Json.parse should be counted as JSON object. Also distinguish what is a JSON string and what is a JSON object.

header('content-type:application:json;charset=utf8');
This header, the browser to the results as JSON directly parse the

One is a string, one is JSON, nothing is different ... It's the right conversion.

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