保存数据的一系列方法

/*======================================================= 
NSKeyedArchiver 
========================================================*/ 
NSString *str = @"abc"; 
NSString *astr = @"efg"; 
NSArray *Array = [NSArray arrayWithObjects:str, astr, nil]; 
      
//Save 
NSString *Path = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0]; NSString *filename = [Path stringByAppendingPathComponent:@"test"]; 
[NSKeyedArchiver archiveRootObject:Array toFile:filename]; 
      
str = @"a"; 
astr = @""; 
      
//load 
NSArray *arr = [NSKeyedUnarchiver unarchiveObjectWithFile: filename]; 
str = [arr objectAtIndex:0]; 
astr =  [arr objectAtIndex:1]; 
      
NSLog(@"str:%@",str); 
NSLog(@"astr:%@",astr); 
     
     
 
/*======================================================= 
NSUserDefaults 
========================================================*/ 
NSString *str = @"abc"; 
NSString *astr = @"efg"; 
NSArray *Array = [NSArray arrayWithObjects:str, astr, nil]; 
      
//Save 
NSUserDefaults *SaveDefaults = [NSUserDefaults standardUserDefaults]; 
[SaveDefaults setObject:Array forKey:@"SaveKey"]; 
      
str = @"a"; 
astr = @""; 
      
//load 
Array = [SaveDefaults objectForKey:@"SaveKey"]; 
str = [Array objectAtIndex:0]; 
astr = [Array objectAtIndex:1]; 
NSLog(@"str:%@",str); 
NSLog(@"astr:%@",astr); 
     
     
 
 
/*======================================================= 
writeToFile: 
========================================================*/ 
NSString *str = @"abc"; 
NSString *astr = @"efg"; 
NSArray *Array = [NSArray arrayWithObjects:str, astr, nil]; 
     
//Save 
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
NSString *documentsDirectory = [paths objectAtIndex:0]; 
if (!documentsDirectory) { 
    NSLog(@"Documents directory not found!"); 
} 
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:@"Savedatas.plist"]; 
[[NSArray arrayWithObjects:Array,nil] writeToFile:appFile atomically:NO];     
     
     
//load 
if([[NSFileManager defaultManager] fileExistsAtPath:appFile]) 
    self.SaveDataArray = [NSMutableArray arrayWithContentsOfFile:appFile];         
else 
    self.SaveDataArray = [NSMutableArray arrayWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"Savedatas" ofType:@"plist"]]; 
NSArray *strArray = [self.SaveDataArray objectAtIndex:0]; 
     
str = [strArray objectAtIndex:0]; 
astr = [strArray objectAtIndex:1]; 
 
 
 
 
 
//坛子里的，搬过来。。。。。 
-(BOOL) writeApplicationData:(NSDictionary *)data  writeFileName:(NSString *)fileName 
{ 
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; 
    if (!documentsDirectory) { 
        NSLog(@"Documents directory not found!"); 
        return NO; 
    } 
    NSString *appFile = [documentsDirectory stringByAppendingPathComponent:fileName]; 
    return ([data writeToFile:appFile atomically:YES]); 
} 
 
-(id) readApplicationData:(NSString *)fileName 
{ 
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; 
    NSString *appFile = [documentsDirectory stringByAppendingPathComponent:fileName]; 
    NSDictionary *myData = [[[NSDictionary alloc] initWithContentsOfFile:appFile] autorelease]; 
    return myData; 
} 

另外可见 

详解Objective-C归档问题解决