如何将NSMutableArray保存到iphone中的plist中

时间:2012-02-20 06:15:23

标签: iphone objective-c plist

我是iphone的新手,我想将NSMutableArray数据保存到plist文件中,我的代码是:

NSArray *array = [[NSArray alloc] initWithArray:self.artistDetailsArray];
[self.artistDetailsArray writeToFile:self.path atomically:YES];

但它在我的plist路径中显示0个元素。请任何帮助我。

提前致谢:

  

以下是我将数据存储到plist和NSUserDefault的代码。   它们都不适用于NSMutableArray / NSArray,但适用于NSString。是否存在plist或UserDefault中存储的最大大小限制?   NSMutableArray仅包含NSDictionary的文本/集。

请建议我。

- (void)initialiseDataFromLocalStorage
{
       NSFileManager *fileManager = [NSFileManager defaultManager];
       NSError *error;
       NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
       NSString *documentsDirectory = [paths objectAtIndex:0];
       self.path = [documentsDirectory stringByAppendingPathComponent:@"saveLogin.plist"];
       if ([fileManager fileExistsAtPath:self.path] == NO) {
               NSString *pathToDefaultPlist = [[NSBundle mainBundle] pathForResource:@"saveLogin" ofType:@"plist"];
               if ([fileManager copyItemAtPath:pathToDefaultPlist toPath:self.path error:&error] == NO) {
                       NSAssert1(0,@"Failed with error '%@'.", [error localizedDescription]);
               }
       }

   // To get stored value from .plist
       NSDictionary *dict = [[NSDictionary alloc]initWithContentsOfFile:self.path];
       self.ResumedataDictionary = [[NSMutableDictionary alloc]initWithDictionary:dict];
       [dict release];
   self.artistDetailsArray = [[NSMutableArray alloc] initWithArray:[self.ResumedataDictionary objectForKey:@"artistDetailsDict"]];    
   // To get stored value from NSUserDefault
   NSUserDefaults *fetchData = [NSUserDefaults standardUserDefaults];
   self.artistDetailsArray = [fetchData objectForKey:@"artistDetailsDict"];    
}        

-(void)saveDataToLocalStorage
{    
   // To store value into .plist
   NSArray *array = [[NSArray alloc] initWithArray:self.artistDetailsArray];
   [ResumedataDictionary setObject:array forKey:@"artistDetailsDict"];
       [ResumedataDictionary writeToFile:self.path atomically:YES];  

   // To store value into NSUserDefault
   NSUserDefaults *fetchData = [NSUserDefaults standardUserDefaults];
   [fetchData setObject:self.artistDetailsArray forKey:@"artistDetailsDict"];    
}

4 个答案:

答案 0 :(得分:5)

NSMutableArray *array=[[NSMutableArray alloc] init];
    [array addObject:@"test"];
    [array writeToFile:@"/Users/parag/test.plist" atomically:YES];
    [array release];

NSMutableArray *array=[[NSMutableArray alloc] init];
[array addObject:@"test121"];
id plist = [NSPropertyListSerialization dataFromPropertyList:(id)array                            format:NSPropertyListXMLFormat_v1_0 errorDescription:@error];


 [plist writeToFile:@"/Users/parag/test.plist" atomically:YES];

查看Creating Property Lists Programmatically

答案 1 :(得分:4)

查看此代码,该代码在文档目录中创建plist的路径:

NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); //1
NSString *documentsDirectory = [paths objectAtIndex:0]; //2
NSString *path = [documentsDirectory stringByAppendingPathComponent:@"data.plist"]; //3

NSFileManager *fileManager = [NSFileManager defaultManager];

if (![fileManager fileExistsAtPath: path]) //4
{
NSString *bundle = [[NSBundle mainBundle] pathForResource:@”data” ofType:@”plist”]; //5

[fileManager copyItemAtPath:bundle toPath: path error:&error]; //6
}

1)创建路径列表。

2)从列表中获取文档目录的路径。

3)创建完整的文件路径。

4)检查文件是否存在。

5)获取之前在bundle目录中创建的plist的路径(通过Xcode)。

6)将此plist复制到您的文档目录。

下次阅读数据:

NSMutableDictionary *savedStock = [[NSMutableDictionary alloc] initWithContentsOfFile: path];

//load from savedStock example int value
int value;
value = [[savedStock objectForKey:@"value"] intValue];

[savedStock release];

写数据:

NSMutableDictionary *data = [[NSMutableDictionary alloc] initWithContentsOfFile: path];

//here add elements to data file and write data to file
int value = 5;

[data setObject:[NSNumber numberWithInt:value] forKey:@”value”];

[data writeToFile: path atomically:YES];
[data release]

答案 2 :(得分:3)

您可以使用属性列表(NSPropertyListSerialization或writeToFile:way)。 但请确保您的数组仅包含有效的属性列表对象(NSString,NSNumber,NSData,NSArray或NSDictionary对象),并且NSDictionary仅包含NSString键。自定义(复杂)对象必须表示为字典。

或者您应该通过NSCoding协议使用归档http://developer.apple.com/library/ios/#documentation/Cocoa/Conceptual/Archiving/Archiving.html。 好的指南在这里http://cocoadevcentral.com/articles/000084.php

答案 3 :(得分:0)

NSData *serializedData;
        NSString *error;
        serializedData = [NSPropertyListSerialization dataFromPropertyList:YourArray(You can use dictionaries.strings..and others too)
        format:NSPropertyListXMLFormat_v1_0 errorDescription:&error];
        if (serializedData) {
        // Serialization was successful, write the data to the file system // Get an array of paths.

       NSArray *documentDirectoryPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
        NSString *docDir = [NSString stringWithFormat:@”%@/serialized.xml”,
         [documentDirectoryPath objectAtIndex:0]];
        [serializedData writeToFile:docDir atomically:YES];
 }
        else {
        // An error has occurred, log it
        NSLog(@”Error: %@”,error); }
        }