save file with fixed file extension

[abue]

Hello,

in my programme the user should put in the name of a file which will be saved. The file extension name should be automatically added to

the file name, example:

the user put in "Log0001" and the complete file name is "log0001.csv"

I tried the following function:

for type I used  a constant with ".csv", but this doesn't work, the error message was: "Set file and program type in Param-nethos.vi<APPEND>
Logg0001"

Is this the right function for my requirement or are there other possibilities?

[crossrulz]

Just use Concatenate String to add ".csv" to the file name and then build the path as you do now.  Then you can create/replace/open the file.

[abue]

Hello crossrulz,

thank you for your replay.

But how could I adding the extension using the base path control?

I tried the 'Build Path' function, but this doesn't work:

[RTSLVU]

Try something like this:

Also note that this does not check for illegal characters in the path or name

[Wes_P]

Build Path adds another layer to your path. The file path you would get out of that would be something like:

..\some_base_path\.txt

Convert the path to a string, and use the Concatenate Strings function to add the .csv to the end of the file name. Alternatively, you could use the File Dialog express VI to put up a dialog for the user. Using that, you can specify a default file type. Depends on your use case.

[GerdW]

Hi Wes,

---

@Wes_P wrote:

Convert the path to a string, and use the Concatenate Strings function to add the .csv to the end of the file name.

---

No!

Don't convert the whole path to a string just to manipulate a filename! That's where StripPath/BuildPath come into play!

(Converting a full path to string may/will fail once you run the code on a different target, like changing from Windows to MacOS or LinuxRT!)

[Wes_P]

Great point. And I completely agree - the benefits of using the path file type and associated functions for cross platform (or even cross-locale within windows) are super important. I was responding the the above comment in mind - using Concatenate Strings. That function won't work on paths, hence the conversion. But 100%, only convert the piece of the path you need, using strip and build path.

I suspect though that the file name comes into the application as a string from user input, so in that case the extension should be added before a full path is ever created.

[BertMcMahan · Accepted solution]

I think he meant, don't convert the whole string to a path. Using Strip Path returns just the filename as a string. Example:

And if you want to be extra safe, use "Get file extension" instead of "Strip path":

This method will take "C:\MyTest.txt" and turn it into "C:\MyTest.csv". The "strip path" method would return "C:\MyTetst.txt.csv".

[Coddiwomple]

I am working on Win7 using LabVIEW18. But hopefully this can help you.

I simply use a build path function. Wire your path into the upper terminal. On the front panel place a string control(this is where your user will input their file name). On your block diagram use a concatenate string to append the file name and extension together. Wire those into your build path. You can double check the outcome using an indicator before moving forward. Then I use the open file function, with a constant of your choosing(whatever is needed in your situation), for the example below I used Create/Replace. I wrote to the file and then closed the file, saving it to the path name created earlier. 

I hope this helps.

[abue]

thank you very much for your support, i decided to use BertMcMahan's last solution.

This is perfect for me.