Need RegExp for image file validation

[paulmcnally]

Hi,

I need a javascript RegExp for image file validation from a file upload
form.

I need to allow image files only (jpeg/jpg/gif/png)

can anybody help me please?

thanks,

Paul.

 

[Evertjan.]

wrote on 24 sep 2006 in comp.lang.javascript:

I need a javascript RegExp for image file validation from a file upload
form.

need != want

I need to allow image files only (jpeg/jpg/gif/png)

Extention testing != file testing

can anybody help me please?

var isImageExtention = /.\.(jpe?g||gif||png)$/i.test(t);

Not tested.

 

[Elegie]

var isImageExtention = /.\.(jpe?g||gif||png)$/i.test(t);

....which allows ghost extension, too

Not tested.

Me neither, shame on us, coffee break?

 

[Evertjan.]

Elegie wrote on 24 sep 2006 in comp.lang.javascript:

...which allows ghost extension, too

Please explain.

Me neither, shame on us, coffee break?

No coffee, why are you not tested?

 

[Elegie]

Please explain.

alert(/.\.(jpe?g||gif||png)$/i.test("foo."));

The syntax of regular expressions defines a single pipe as separator for
alternatives, doubling them results in your final production allowing no
extension at all.

No coffee, why are you not tested?

They weren't that friendly so I escaped

Cheers.

 

[Evertjan.]

Elegie wrote on 24 sep 2006 in comp.lang.javascript:

alert(/.\.(jpe?g||gif||png)$/i.test("foo."));

The syntax of regular expressions defines a single pipe as separator for
alternatives, doubling them results in your final production allowing no
extension at all.

That's why I didn't test ;-{