how to use stringWithContentsOfFile for reading image in ios

Question

I am getting an error while using the following method for reading image.

[NSString stringWithContentsOfFile:imagepath encoding:NSUTF8StringEncoding error:&error

The error is The file “image.png” couldn’t be opened using text encoding Unicode (UTF-8).

What exactly do you want to achieve? Sounds a bit strange to me to load a png image into a string ;-) — d4Rk, Dec 26 '18 at 11:16
@d4Rk I want to send an image to a server with string format — Pratik, Dec 26 '18 at 11:27

vadian · Answer 1 · 2018-12-26T11:38:52.943

0

An image is always saved as NSData not as string

NSData *data = [NSData dataWithContentsOfFile:imagepath options:0 error:&error];

For sending the data to a server create a string for example base64 encoded but this depends on what format the server expects

if (data != nil) {
   NSString *string = [data base64EncodedStringWithOptions:0];
}

edited Dec 26 '18 at 11:38

answered Dec 26 '18 at 11:16

vadian

I'm not sure, what he wants.. could also be a base64 encoded string or whatever ;-) – d4Rk Dec 26 '18 at 11:29
@d4Rk A base64 encoded string doesn't cause this error and `.png` points to an image file. – vadian Dec 26 '18 at 11:30
Ok, what about it is saved as data, and he wants do send it to the backend as base64? I would not do it like that, but totally possible, isn't it? – d4Rk Dec 26 '18 at 11:31
@d4Rk To *read* the file you have to use the `NSData` API anyway (or `UIImage` to create an image). – vadian Dec 26 '18 at 11:33
Whatever, just wanted to make my point, that it is totally not clear what he wants to do. (despite loading a image first) – d4Rk Dec 26 '18 at 11:34
@d4Rk I want to send an image to a server with string format – Pratik Dec 26 '18 at 11:36

1 Answers1