I want to upload many items at once in a Toolset Form (former CRED Form), but I there does not seem to be any feature to upload more than one item a time to my File Fields, or to edit it in any way during the upload, such as used to from the WordPress Upload mechanism
Natively that's not possible with Toolset Forms (Former CRED), but we do have a Feature request filed that will solve this in one strike. We plan to add the native WordPress Media uploader to any form of upload mechanism in CRED. This will basically allow you to do whatever you can do in WordPress, but using CRED.
That's thou not to be implemented so soon. It will require some time, as for now, only custom code can solve this. I suggest to contact the contractors in case you need help with that, as we do not have any working examples of such elaborated custom code. https://toolset.com/contractors/
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