Strange characters in LUA strings

TSG · Post by **TSG** » 21 Jan 2012 08:21

This maybe a LUA bug rather than FH but if I do:

fhSetValueAsText(objFILE, 'C:UsersTestPicturesbag.jpg')

LUA sets the objFILE value to:

C:UsersTestPictures[?]ag.jpg

(where ? is a strange character rendered as a black box with a circle in it)

This can be seen in the debug variables window and is also the value put into the multimedia record in FH.

ID:5836

TSG · Post by **TSG** » 21 Jan 2012 08:22

PS: I have only noticed this since 5.0.0.5. I *believe* it was working OK before but cannot guarantee it.

Post by **SimonOrde** » 21 Jan 2012 10:13

This isn't a bug - it's a feature of Lua. Within Lua, the backslash character '' has a special role in strings (as it does in other programming languages like C and C++). For example, 'n' means the newline character and 't' means a tab character. If you want to put a backslash into a string, you have to double it up to remove its special meaning. i.e. the line you needed was this:

fhSetValueAsText(objFILE, 'C:\Users\Test\Pictures\bag.jpg')

If you use that, the correct value 'C:UsersTestPicturesbag.jpg' will be inserted.

In case anyone reading this doesn't know what a 'string' is, incidentally, it means text in quotes.

YouTube · Post by **Jane** » 21 Jan 2012 11:32

Just to add to this, the escaping of the is only needed if you are entering the string directly in the source code, if you are prompting for a file name or obtaining it from iup.getfile or similar it can be entered as normal.

This is detailed on the Lua Quickstart page in the plugin help.

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