Why eval fails here?

问题

0001: response
$[0] = [string] "{\"code\":200,\"id\":121}"
0001: eval(response)
SyntaxError: invalid label

Anyone knows?

回答1:

You have to wrap it in () to trigger expression evaluation, like this:

eval("(" + response + ")")

You can test it out here.

---

Though a better method is native JSON handling:

var result = JSON.parse(response);

Just include json2.js for older browser (< IE8) support, the call is the same...it just adds the global JSON object if it's missing.

回答2:

You need to wrap the JSON string in parentheses.

Otherwise, the { ... } is interpreted as a block of executable statements, which it isn't.

By surrounding it in parentheses, you force the interpreter to interpret it as an expression.

来源：https://stackoverflow.com/questions/4305003/why-eval-fails-here