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Best way to prevent forbidden characters

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Posted on by ConnM

260

Hello

I have been trouble shooting occasional errors in my flow. The user enters text in a SharePoint field and a folder is generated after that.

It had been giving me BadRequests, but a trim operation removed any trailing spaces and it worked great, until it the issue started again.

As it turns out there are also forbidden characters, (:, /, ...) being used.

I naturally think a replace operation could screen out the characters, but it would be a mess. Is there a more elegant solution?

Regards

Conn

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trice602 13,773 Super User 2025 Season 1 on at

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Re: Best way to prevent forbidden characters

Hi @ConnM ! Nice! Always glad to help and get this feedback on a Monday morning 🙂
ConnM 260 on at

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Re: Best way to prevent forbidden characters

Thanks @trice602

This is brilliant. I'll get this in ASAP

Really appreciate it
Conn
trice602 13,773 Super User 2025 Season 1 on at

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Re: Best way to prevent forbidden characters

Note: you would replace "test" above with your dynamic content.
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trice602 13,773 Super User 2025 Season 1 on at

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Re: Best way to prevent forbidden characters

Hi @ConnM ,

One thing that I have done is insert a compose and replace the illegal characters with an "_" or remove it completely. Here's a sample replace expression to remove the most common characters:

replace(replace(replace(replace(replace(replace(replace(replace(replace(replace(test, '\\', ''), '/', ''), ':', ''), '*', ''), '?', ''), '"', ''), '<', ''), '>', ''), '|', ''), '&', ''), '#', '')

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