How To Read And Write On A File In Same Time Using C#

Question

i want to know how to read file and write on it in the same time for example:

file content:

Johny
tony
jack
Ahmad
Johny

string line;

line = file.ReadLine();

if (line == "johny")
{
   line= "Sam"
}

Read the content into an array/list first, Then replace the text as you want and then overwrite the file. — Kurubaran, Aug 12 '15 at 23:22
Yes thank you i think that's is the easy way to do this ... i will try with a list — Youssef Omri, Aug 12 '15 at 23:47

score 1 · Accepted Answer · answered Aug 12 '15 at 23:12

You have to bear in mind that "Sam" and "Johnny" are not the same length. What will the file do with those empty bytes? Worse, what if you replaced "Sam" with "Johnny"? You will overwrite letters in the next record.

Fixed-width records can address this, but for a small file system, I would just read all into a list, then rewrite the whole list to file again. Or a different approach would be to set it all up in a database and let the database handle the reads and writes and you handle the business logic.

But just writing new data to a file on the fly as you are reading it is probably going to be more trouble than it's worth.

C# makes read/write access to a file a pain even with fixed width records. — Loren Pechtel, Aug 13 '15 at 03:47

How To Read And Write On A File In Same Time Using C#

file content:

1 Answers1