Read and Write the same file

Ian Clark turbana at gmail.com
Tue May 1 19:28:00 EDT 2007


On 1 May 2007 16:03:28 -0700, JonathanB <doulos05 at gmail.com> wrote:
> Ok, so this is the scenario. I need to create a simple, no-frills XML
> editor for non-technical users. It doesn't have to do anything fancy,
> what I want is a series of text boxes with the text contents of the
> elements pre-printed. Then the users can type their changes into the
> text boxes and click submit and it will load the changes in. So here
> is the problem, this means I need to open the same file as both read
> and write. How do I do this? I'm slowly learning the DOM stuff that I
> need to know to do this, but this file thing I haven't been able to
> find anywhere.
>
> JonathanB

Well the most straight forward approach is to read data from the file
into memory. Let the user make any changes. Then save the data back to
the file, overwriting the oringinal copy. Now, this only really works
if you're dealing with small files.

Regardless though, you never really need to have a file open for both
reading and writing. Since they occur (so it sounds) at distinct times
during your program flow, just open it twice: the first to read, the
second to write.

Ian



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