问题
Can Javascript get a function as text? I'm thinking like the inverse of eval().
function derp() { a(); b(); c(); }
alert(derp.asString());
The result would be something like "a(); b(); c();"
Does it exist?
回答1:
Updated to include caveats in the comments below from CMS, Tim Down, MooGoo:
The closest thing available to what you're after is calling .toString() on a function to get the full function text, like this:
function derp() { a(); b(); c(); }
alert(derp.toString()); //"function derp() { a(); b(); c(); }"
You can give it a try here, some caveats to be aware of though:
- The
.toString()on function is implementation-dependent (Spec here section 15.3.4.2)- From the spec: An implementation-dependent representation of the function is returned. This representation has the syntax of a FunctionDeclaration. Note in particular that the use and placement of white space, line terminators, and semicolons within the representation string is implementation-dependent.
- Noted differences in Opera Mobile, early Safari, neither displaying source like my example above.
- Firefox returns a compiled function, after optimization, for example:
(function() { x=5; 1+2+3; }).toString()==function() { x=5; }
回答2:
function derp() { a(); b(); c(); }
alert(derp.toString());
来源：https://stackoverflow.com/questions/3379875/can-javascript-get-a-function-as-text