C# the maximum size of data for multiple files

Question

I would like block the upload files over 10mb? not about the maximum size of a single file. How to do it ? Any help and code samples would be very appreciated. Thanks!

do you mean 10Mb max for an upload (over 1 or more files). Or do you mean 10Mb in total, ever. For example, would I be allowed to upload 1Mb file 11 times? — Dave Becker, Mar 07 '17 at 11:19
Does this help: http://stackoverflow.com/questions/19038390/uploading-multiple-files-mvc-is-there-a-total-file-size-limit — Dave Becker, Mar 07 '17 at 11:31

score 0 · Answer 1 · answered Mar 07 '17 at 14:09

Simply, there's no way to do what you want server-side. You can only limit individual file size, not the size of a full collection of files. While you could add some server-side validation to check the full size of all the files combined, by that point, the damage is already done: the server has already accepted the full upload, so you might as well do something with it, instead of simply returning an error.

HTML5, however, affords you a client-side solution, but the standard caveats apply. First, the solution will be JavaScript-based, and as with any JS, it can be disabled or tampered with. Second, it requires JS APIs only available in modern browsers, so it will be completely ineffective in IE 7-10.

$('#MyFileInput').on('change', function () {
    var totalSize = 0;
    for (var i = 0; i < this.files.length; i++) {
        totalSize += this.files[i].size;
    }

    if (totalSize > 10 * 1024 * 1024) {
        // present error to user
    }
});

C# the maximum size of data for multiple files

1 Answers1