Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
Summary
Outputs a warning message to the Web Console.
Note: In Firefox, warnings have a small exclamation point icon next to them in the Web Console log.
Syntax
console.warn(obj1 [, obj2, ..., objN); console.warn(msg [, subst1, ..., substN);
Parameters
-
obj1...objN - A list of JavaScript objects to output. The string representations of each of these objects are appended together in the order listed and output.
-
msg - A JavaScript string containing zero or more substitution strings.
-
subst1...substN -
JavaScript objects with which to replace substitution strings within
msg. This gives you additional control over the format of the output.
See Outputting text to the console in the documentation of console for details.
Specification
Not part of any specification.
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | (Yes) | 4.0 (2.0) | 8 | (Yes) | (Yes) |
| Substitution strings | ? | 9.0 (9.0) | ? | ? | ? |
| Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | ? | 4.0 (2.0) | ? | ? | ? |
| Substitution strings | ? | 9.0 (9.0) | ? | ? | ? |