If users browser is set to always ask for DL destination, you can upload the string to server, create a temp file and DL that.
While reading from local disk is considered less of a risk, I believe current HTML/browaser implementations forbid that due to security concerns.

Or are you thinking of a non-Browser client like Node?

>Hi everybody,
>
>I'm working on a User Story that has the following requirement: when I click on a button, the Save As dialog should popup and when the user selected a location, a file should be generated (tab delimited file) and saved in that location.
>
>I did a quick google search and I don't see as what I am supposed to implement. I'm using angularJS for front-end development and ASP.NET MVC for server side development.
>
>Thanks in advance.
>
>In other words, I have the following few VFP lines and I need to re-create that functionality from the browser:
>

>lcFile = PUTFILE("Name the RGIS Validation file to export to.","RGIS_Validation_" + ;
>                    DTOC(DATE(), 1) + ".txt", "txt,dat")
>   if ! empty(lcFile)
>	   COPY TO (lcFile) DELIMITED WITH TAB
>	   MESSAGEBOX('RGIS Validation file created.', 0, 'Tallyman Notification')
>	 endif