just noticed that when making a list, the return value of an empty textbox.text is not considered an element of the list. What does textbox.Text return when it's empty? I thought even an empty string or Null would still be considered an element in the list. Thanks
Please download and post each of those event block(s)/procedures here ...
(sample video)
I expect to get ['a','','c'] but i get ['a', 'c'], it appears that it does not even return a Null value, not an empty string.
Thanks. I need the item with single quotes, the reason is that Im updating the string to mysql, when the value for one item is empty without quote, when you GET it and in the result of the query, it will be missing a column. for example:
UPDATE x SET a='a', b=' ', c= , d='d' WHERE ....
the database will look like:
a b c d
a Null d
When you get it, it will be [a, Null, d]
This will cause error when you, e.g. retrieve the 4th element of the array
Thanks a lot for the detailed explaination, but it does not seem to return an empty string for me in my operation, Im trying to put the returned value in single quotes, it becomes nothing (don't know what nothing means here)
i think the problem is that i do not get the string ['a','','c'], instead i get ['a','c']
Its a list, not a string.
From where?
Show all relevant blocks.
see my reply to TIMAI2, it's from the output of a mysql GET query. again the issue is: i try to single quote the return of an empty textbox.Text, then send it to mysql, when i GET query mysql, it completely ignores that value (not returning a Null, nor an empty string) as if that column does not exist.
Like this ?
You shouldn't use ' when working with MySQL in App Inventor. I'll suggest to use ` instead.
It does depend on what you are doing....
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not the same thing? TIMAI2's link says use backticks for column names though
Thanks for the info, but here we have 'a,,c', looks like it's also equivalent to 'ac', but that is the problem now.
None of our examples return 'a',,'c' ?
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i am not sure that textbox will always be empty, so i cannot artificially create an empty string, instead i would have to put a single quote before .gettext and another after it, this would probably be the same thing as i did before with ',' as the separator
Post a simple test aia (to shorten it).