直接上代碼：
.h文件：
[cpp] #import <Foundation/Foundation.h> 
#define DEFAULT_DATE_TIME_FORMAT (@"yyyy-MM-dd'T'HH:mm:ss'Z'") 
#define DEFAULT_DATE_FORMAT (@"yyyy-MM-dd") 
#define DEFAULT_TIME_FORMAT (@"HH:mm:ss'Z'") 
 
@interface FileUtils : NSObject { 
     
} 
 
+(NSString*) settingPath; 
+(NSString*) cachePath; 
+(BOOL) clearCache:(NSError**)error; 
+(NSString*) fileAtBundleResource:(NSString*)file; 
+(BOOL) fileExist:(NSString*)file; 
+(BOOL) fileExistAtCache:(NSString*)file; 
+(NSString*) cachedFile:(NSString*)file; 
+(BOOL) writeToFile:(NSString*)fileWithPath withData:(NSData*)data; 
+(BOOL)deleteFile:(NSString*)fileWithPath; 
+(NSString*) documentPathWith:(NSString*)cmp; 
@end 
 
 
@interface ValueUtils : NSObject { 
     
} 
+(BOOL) isEmpty:(NSString*)text; 
+(BOOL) boolValue:(NSDictionary*)dict forKey:(id)key; 
+(float) floatValue:(NSDictionary*)dict forKey:(id)key; 
+(NSInteger) intValue:(NSDictionary*)dict forKey:(id)key; 
+(NSString*) stringValue:(NSDictionary*)dict forKey:(id)key; 
+(NSArray*) arrayValue:(NSDictionary*)dict forKey:(id)key; 
+(id) noneNullValue:(NSDictionary*)dict forKey:(id)key; 
+(NSDictionary*) dictionaryValue:(NSDictionary*)dict forKey:(id)key; 
+(BOOL) stringEquals:(NSString*)str1 to:(NSString*)str2; 
+(BOOL) caseEquals:(NSString*)str1 to:(NSString*)str2; 
+(NSString*) refineUrl:(NSString*)url; 
+(BOOL) isURLString:(NSString*)text; 
+(BOOL) startWith:(NSString*)prefix forString:(NSString*)text; 
+(BOOL) endWith:(NSString*)suffix forString:(NSString*)text; 
+(NSDate *)stringToDate:(NSString *)string withFormat:(NSString*)fmt; 
+(NSString*) dateToString:(NSDate*)date withFormat:(NSString*)fmt; 
+(NSString*) idToString:(id)obj; 
+(BOOL)  booleanToBool:(id)bobj; 
@end 

.m文件：
[cpp] view plaincopy
#import "FileUtils.h" 
#import "CJSONDeserializer.h" 
#import "CJSONSerializer.h" 
 
@implementation FileUtils 
 
+(NSString*) settingPath 
{ 
    ////Make a new director 
    NSFileManager *fileManager = [NSFileManager defaultManager]; 
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; 
     
    documentsDirectory = [documentsDirectory stringByAppendingPathComponent:@".settings"]; 
     
    BOOL folder = NO; 
    BOOL exist = [fileManager fileExistsAtPath:documentsDirectory isDirectory:&folder]; 
    if ( exist == YES && folder == YES ) { 
        return [documentsDirectory stringByAppendingPathComponent:@"measets.ini"]; 
    }else{ 
        NSError* error = nil; 
        [fileManager createDirectoryAtPath:documentsDirectory  
               withIntermediateDirectories:YES 
                                attributes:nil 
                                     error:&error]; 
        if( error != nil ){ 
            NSLog(@"Can not create directory %@.  Error is %@.", documentsDirectory, 
                  [error description]); 
            return nil; 
        } 
        return documentsDirectory; 
    } 
    /***
     NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
     NSString *documentsDirectoryPath = [paths objectAtIndex:0];
     NSString *secondaryDirectoryPath = [documentsDirectoryPath stringByAppendingPathComponent:@"secondary"];
     NSString *databaseFile = [secondaryDirectoryPath stringByAppendingPathComponent:@"database.db"];
     
     NSFileManager *fileManager = [NSFileManager defaultManager];
     [fileManager removeItemAtPath:databaseFile error:NULL];
     ***/ 
} 
 
+(BOOL) fileExist:(NSString*)file 
{ 
    NSFileManager *fileManager = [NSFileManager defaultManager]; 
    return [fileManager fileExistsAtPath:file]; 
} 
 
+(NSString*) fileAtBundleResource:(NSString*)file 
{ 
    return [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:file]; 
} 
 
+(BOOL) fileExistAtCache:(NSString*)file 
{ 
    return [self fileExist:[self cachedFile:file]]; 
} 
 
+(NSString*) cachedFile:(NSString*)file 
{ 
    NSString* fileAtCache = [NSString stringWithFormat:@"%@%@",[self cachePath], file]; 
    return fileAtCache; 
} 
 
+(BOOL) writeToFile:(NSString*)fileWithPath withData:(NSData*)data 
{ 
    BOOL folder = NO; 
    NSFileManager *fileManager = [NSFileManager defaultManager]; 
     
    NSString* fileName = [fileWithPath lastPathComponent]; 
    NSInteger toIndex = [fileWithPath length] - [fileName length]; 
    NSString* path = [fileWithPath substringToIndex:toIndex]; 
    BOOL exist = [fileManager fileExistsAtPath:path isDirectory:&folder]; 
    if (  exist != YES ) { 
        NSError* error = nil; 
        [fileManager createDirectoryAtPath:path  
               withIntermediateDirectories:YES 
                                attributes:nil 
                                     error:&error]; 
        if( error != nil ){ 
            NSLog(@"Can not create directory %@.  Error is %@.", path, 
                  [error description]); 
            return NO; 
        } 
    } 
    if ( data != nil ) { 
        return [data writeToFile:fileWithPath atomically:YES];  
    } 
    return NO; 
} 
 
+(NSString*) documentPathWith:(NSString*)cmp 
{ 
    ////Make a new director 
    NSFileManager *fileManager = [NSFileManager defaultManager]; 
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; 
     
    documentsDirectory = [documentsDirectory stringByAppendingPathComponent:cmp]; 
     
    BOOL folder = NO; 
    BOOL exist = [fileManager fileExistsAtPath:documentsDirectory isDirectory:&folder]; 
    if (  exist == YES && folder == YES ) { 
        return documentsDirectory; 
    }else{ 
        NSError* error = nil; 
        [fileManager createDirectoryAtPath:documentsDirectory  
               withIntermediateDirectories:YES 
                                attributes:nil 
                                     error:&error]; 
        if( error != nil ){ 
            NSLog(@"Can not create directory %@.  Error is %@.", documentsDirectory, 
                  [error description]); 
            return nil; 
        } 
        return documentsDirectory; 
    } 
} 
 
+(NSString*) cachePath 
{ 
    ////Make a new director 
    NSFileManager *fileManager = [NSFileManager defaultManager]; 
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; 
     
    documentsDirectory = [documentsDirectory stringByAppendingPathComponent:@".caches"]; 
     
    BOOL folder = NO; 
    BOOL exist = [fileManager fileExistsAtPath:documentsDirectory isDirectory:&folder]; 
    if (  exist == YES && folder == YES ) { 
        return documentsDirectory; 
    }else{ 
        NSError* error = nil; 
        [fileManager createDirectoryAtPath:documentsDirectory  
               withIntermediateDirectories:YES 
                                attributes:nil 
                                     error:&error]; 
        if( error != nil ){ 
            NSLog(@"Can not create directory %@.  Error is %@.", documentsDirectory, 
                  [error description]); 
            return nil; 
        } 
        return [documentsDirectory stringByAppendingPathComponent:@"measets.ini"]; 
    } 
} 
 
+(BOOL)deleteFile:(NSString*)fileWithPath 
{ 
    NSFileManager *fileManager = [NSFileManager defaultManager]; 
    NSError* error = nil; 
    BOOL ret = [fileManager removeItemAtPath:fileWithPath error:&error]; 
    if ( error != nil ) { 
        NSLog(@"DeleteFile with an error: %@.", [error description]); 
    } 
    return ret; 
} 
 
+(BOOL) clearCache:(NSError**)error 
{ 
    NSFileManager *fileManager = [NSFileManager defaultManager]; 
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; 
    documentsDirectory = [documentsDirectory stringByAppendingPathComponent:@".caches"]; 
    [fileManager removeItemAtPath:documentsDirectory error:error]; 
    return YES; 
} 
 
@end 
 
 
@implementation ValueUtils 
 
+(BOOL) isEmpty:(NSString*)text 
{ 
    if (text == nil) { 
        return YES; 
    } 
    if ([text length] == 0 ) { 
        return YES; 
    } 
    return NO; 
} 
 
+(NSString*) idToString:(id)obj 
{ 
    if ( obj == nil ) { 
        return nil; 
    } 
     
    if ( [obj isKindOfClass:[NSNull class]]) { 
        return nil; 
    } 
     
    if ( [obj isKindOfClass:[NSString class]]) { 
        return (NSString*)obj; 
    }else if ( [obj isKindOfClass:[NSArray class]] ){ 
        NSMutableString* ntf = [NSMutableString string]; 
        for (id t in obj ) { 
            [ntf appendString:[self idToString:t]]; 
            [ntf appendString:@","]; 
        } 
        return ntf; 
    }else { 
        if( CFGetTypeID(obj) == CFBooleanGetTypeID() ){ 
            return [NSString stringWithFormat:@"%@", (CFBooleanGetValue((CFBooleanRef)obj) == true ? @"true" : @"false") ]; 
        } 
        if ( sizeof(obj) == sizeof(BOOL) ) { 
            //return (BOOL)obj == YES ? @"true" : @"false"; 
        } 
        if( [obj respondsToSelector:@selector(stringValue)] ){ 
            return [obj stringValue]; 
        } 
        return [obj description]; 
    } 
} 
 
+(BOOL) boolValue:(NSDictionary*)dict forKey:(id)key 
{ 
    id bl = [dict objectForKey:key]; 
    if ( bl == nil || [bl isKindOfClass:[NSNull class]]) { 
        return NO; 
    } 
    if ( [bl isKindOfClass:[NSString class]]) { 
        NSString* cstr = [bl lowercaseString]; 
        if ( [cstr isEqualToString:@"yes"] || [cstr isEqualToString:@"true"]) { 
            return YES; 
        } 
        return [cstr boolValue]; 
    } 
    if ( CFBooleanGetValue((CFBooleanRef)bl) ) { 
        return YES; 
    } 
    return NO; 
} 
 
+(float) floatValue:(NSDictionary*)dict forKey:(id)key{ 
    id bl = [dict objectForKey:key]; 
    if ( bl == nil || [bl isKindOfClass:[NSNull class]]) { 
        return 0.0f; 
    } 
    return [bl floatValue]; 
} 
 
+(NSInteger) intValue:(NSDictionary*)dict forKey:(id)key 
{ 
    id bl = [dict objectForKey:key]; 
    if ( bl == nil || [bl isKindOfClass:[NSNull class]]) { 
        return 0.0f; 
    } 
    return [bl floatValue];     
} 
 
+(NSString*) stringValue:(NSDictionary*)dict forKey:(id)key 
{ 
    id bl = [dict objectForKey:key]; 
    if ( bl == nil || [bl isKindOfClass:[NSNull class]]) { 
        return nil; 
    } 
    return [self idToString:bl]; 
} 
 
+(NSArray*) arrayValue:(NSDictionary*)dict forKey:(id)key 
{ 
    id bl = [dict objectForKey:key]; 
    if ( bl == nil || [bl isKindOfClass:[NSNull class]]) { 
        return nil; 
    } 
    if ( [bl isKindOfClass:[NSArray class]]) { 
        return (NSArray*)bl; 
    } 
    return nil; 
} 
 
+(NSDictionary*) dictionaryValue:(NSDictionary*)dict forKey:(id)key 
{ 
    id bl = [dict objectForKey:key]; 
    if ( bl == nil || [bl isKindOfClass:[NSNull class]]) { 
        return nil; 
    } 
    return (NSDictionary*)bl; 
} 
 
+(id) noneNullValue:(NSDictionary*)dict forKey:(id)key 
{ 
    id bl = [dict objectForKey:key]; 
    if ( bl == nil || [bl isKindOfClass:[NSNull class]]) { 
        return nil; 
    } 
    return bl; 
} 
 
+(BOOL) stringEquals:(NSString*)str1 to:(NSString*)str2 
{ 
    if ( str1 == nil || str2 == nil ) { 
        return NO; 
    } 
    return [str1 compare:str2 options:NSCaseInsensitiveSearch] == NSOrderedSame; 
} 
 
+(BOOL) caseEquals:(NSString*)str1 to:(NSString*)str2 
{ 
    return (str1 == nil || str2 == nil) ? NO : [str1 isEqualToString:str2]; 
} 
 
+(BOOL) startWith:(NSString*)prefix forString:(NSString*)text; 
{ 
    if ( text != nil && prefix != nil ){ 
        if ( [prefix length] > [text length] ) { 
            return NO; 
        } 
         
        NSString* prestr = [text substringToIndex:[prefix length]]; 
        if ( [self stringEquals:prestr to:prefix] ) { 
            return YES; 
        } 
         
    } 
    return NO; 
} 
 
+(BOOL) endWith:(NSString*)suffix forString:(NSString*)text 
{ 
    if ( text != nil && suffix != nil ){ 
        if ( [suffix length] > [text length] ) { 
            return NO; 
        } 
        NSInteger len = [text length] - [suffix length]; 
        NSString* sufstr = [text substringFromIndex:len]; 
        if ( [self caseEquals:sufstr to:suffix] ) { 
            return YES; 
        } 
         
    } 
    return NO; 
} 
 
+(BOOL) isURLString:(NSString*)text 
{ 
    if ( [text length] > 6 ) { 
        NSString* prefix = [text substringToIndex:6]; 
        if ( [self stringEquals:prefix to:@"http:/"] || [self stringEquals:prefix to:@"https:"] ) { 
            return YES; 
        } else if ( [self stringEquals:prefix to:@"local:" ] ){ 
            return YES; 
        } 
    } 
    if ( [self startWith:@"/" forString:text] ){ 
        return YES; 
    } 
    return NO; 
} 
 
+(NSString*) refineUrl:(NSString*)url 
{ 
    return url; 
} 
 
+(BOOL)  booleanToBool:(id)bobj 
{ 
    if ( bobj == nil ) { 
        return NO; 
    } 
    if ( [bobj isKindOfClass:[NSString class]] ) { 
        return [bobj caseInsensitiveCompare:@"yes"] == 0 || [bobj caseInsensitiveCompare:@"true"] == 0; 
    }else if ( [bobj respondsToSelector:@selector(boolValue)] ){ 
        return [bobj boolValue]; 
    }else { 
        return CFBooleanGetValue((CFBooleanRef)bobj); 
    } 
     
    return NO; 
} 
 
+(NSDate *)stringToDate:(NSString *)string withFormat:(NSString*)fmt{   
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; 
    [formatter setTimeZone:[NSTimeZone defaultTimeZone]]; 
    //#define kDEFAULT_DATE_TIME_FORMAT (@"yyyy-MM-dd'T'HH:mm:ss'Z'") 
    NSString* format = fmt == nil ? DEFAULT_DATE_TIME_FORMAT : fmt; 
    [formatter setDateFormat:format]; 
    NSDate *date = [formatter dateFromString:string]; 
    [formatter release]; 
    return date; 
} 
 
+(NSString*) dateToString:(NSDate*)date withFormat:(NSString*)fmt 
{ 
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; 
    [formatter setTimeZone:[NSTimeZone defaultTimeZone]]; 
    //#define kDEFAULT_DATE_TIME_FORMAT (@"yyyy-MM-dd'T'HH:mm:ss'Z'") 
    NSString* format = fmt == nil ? DEFAULT_DATE_FORMAT : fmt; 
    [formatter setDateFormat:format]; 
    NSString* dateStr = [formatter stringFromDate:date]; 
    [formatter release]; 
    return dateStr; 
} 
@end 



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