Check for a NULL string in Blueprint

Development Programming & Scripting
1

I am using a library that has a method I call from Blueprint that can return a possible error message. Sometimes, it reports that it failed but the error message is NULL. When that happens, I get an exception from the Blueprint when it tries to append that NULL error message to another String.

Is there a node or something I can use to check if a String is null in Blueprints? I know actors have IsValid, is there something similar for the String?

I didn’t see anything, so it maybe that my best recourse is to update the append node to handle NULL inputs without throwing an exception.

Thanks
Eric

2

Hello Eric,

Check the length of the string, length > zero, then you have a string.

Hope this helps,

3

I am doing this with an editor script and it doesn’t return 0, it returns “None”, which is > 0. This is when getting folder path though, so that might be special.

4

IS VALID node checks for empty/null

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5

I can’t do a null-check with editor scripting.
Node doesn’t exist for me.

6

Use ‘Is Empty’ node.

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7

Yeah, but does it do it for every type of data? Because I tried it on a ‘name’ type variable and you can’t connect the pin.

8

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