Question

In .NET, a file can be written to the file system using:

FileStream fs = File.Create(@"Filename");
StreamWriter sw = new StreamWriter(fs);
sw.WriteLine("Hello, World!");
// etc...
sw.Close();
fs.Close();

How would I achieve the same operation in Objective-C and Cocoa? I believe it involves the NSMutableData class, but I do not know how to implement it.

Answer 1

Tiny Mac Tutorials has a post on this.

The example code from that post is below:

// filetest.m
// Created by macateeny.blogspot.com Sept 2008.
// Copyleft (c) 2008. some rights reserved.
// 
// Compile from the command line with:
// gcc filetest.m -Wall -o filetest -framework Foundation
//
#import <Foundation/Foundation.h>

// main entry point of our file test tool with the argument counter and vector
int main(int argc,char *argv[])
{
    // allocate a memory pool for our NSString Objects
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

    // declare NSString Obj pointer and initialise it
    NSString *str = @"Cooking with Objective-C\r\n";

    // declare NSString filename and alloc string value
    NSString *filenameStr = @"./filetest.txt";

    // NSObject which contains all the error information
    NSError *error;

    // write contents and check went ok
    if(![str writeToFile: filenameStr atomically: YES encoding:NSUTF8StringEncoding error:&error]) {
            NSLog(@"We have a problem %@\r\n",[error localizedFailureReason]);
    }

    // unleash the allocated pool smithers
    [pool release];

    // The app is terminated
    return 0;
}