add_meta_box callback receives Post Object with ID a String instead of an Integer

[adiant]

The Post Object received by the Callback Function specified in the add_meta_box function delivers the correct value for ID, but the Type is String, not Integer.

The attached Plugin demonstrates the problem when in the Edit Page Admin panel.

[adiant]

Demonstration Plugin

[dd32]

Unfortunately this is a compatibility thing - All integers from the database are delivered to WordPress as numeric strings, not ints.

Changing the fields to be ints can unfortunately introduce compatibility issues, see #22324 and #22324 for some details on that.

Worth noting here, that you should always expect a numeric string OR integer for post ID's for maximum compatibility.

For example, with the provided code, on a new-page view you'll see it as an int, but on an edit you'll see it as a numeric string.

[adiant]

I agree with your reasoning and will try to update the Codex to make that clear.