The document discusses methods for getting the preferred MIME type for a file from its extension or path. It defines a category on NSString to initialize a string from NSData using an IANA character set name. It also shows code for getting the preferred MIME type by calling UTTypeCopyPreferredTagWithClass on the file's UTI, determined from its extension using UTTypeCreatePreferredIdentifierForTag, or from its path using LSCopyItemAttributes.

1. 2014/2/23
Cocoa
#23
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2. 2014/2/23
Cocoa
#23
@interface NSString ( CocoaStudy23 )
-(id) initWithData:(NSData *)data IANACharSetName:(NSString *)charSetName;
@end
@implementation NSString ( CocoaStudy23 )
-(id) initWithData:(NSData *)data IANACharSetName:(NSString *)charSetName
{
CFStringEncoding cfCharset = CFStringConvertIANACharSetNameToEncoding((CFStringRef)charSetName);
NSStringEncoding nsCharset = CFStringConvertEncodingToNSStringEncoding(cfCharset);
return [self initWithData:data encoding:nsCharset];
}
@end
@implementation AppController
-(void) awakeFromNib
{
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3. 2014/2/23
Cocoa
#23
UInt8 cString[] = { 0x82, 0xA9, 0x82, 0xC8, 0x8A, 0xBF, 0x95, 0x5C, 0 };
NSData *streamedString = [NSData dataWithBytes:(void *)&cString length:sizeof cString];
NSString *testString = [[NSString alloc]initWithData:streamedString IANACharSetName:@"Shift-JIS"];
NSLog( testString );
}
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4. 2014/2/23
Cocoa
#23
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5. 2014/2/23
Cocoa
#23
-(void) awakeFromNib
{
NSString *targetFile = @"/Users/msyk/Documents/apple-reg.pdf";
NSString *prefMIMEType = [self preferedMIMETypeFromFile:targetFile];
NSLog( prefMIMEType );
targetFile = @"file.xls";
prefMIMEType = [self preferedMIMETypeFromFile:targetFile];
NSLog( prefMIMEType );
}
- (NSString *)preferedMIMETypeFromFile:(NSString *)targetFile
{
NSString *currentFileExtension = [targetFile pathExtension];
CFStringRef uti = UTTypeCreatePreferredIdentifierForTag(
kUTTagClassFilenameExtension, (CFStringRef)currentFileExtension, NULL);
CFStringRef prefferdMIMEType = UTTypeCopyPreferredTagWithClass(uti, kUTTagClassMIMEType);
return (NSString *)prefferdMIMEType;
}
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6. 2014/2/23
Cocoa
#23
- (NSString *)preferedMIMETypeFromFile:(NSString *)targetFile
{
FSRef ref;
FSPathMakeRef ((unsigned char*)[targetFile fileSystemRepresentation], &ref, NULL);
CFDictionaryRef values = NULL;
CFStringRef attrs[] = { kLSItemContentType, kLSItemExtension, kLSItemRoleHandlerDisplayName };
CFStringRef prefferdMIMEType = NULL;
CFArrayRef attrNames = CFArrayCreate(NULL, (const void **)attrs, 3 , NULL);
if ( LSCopyItemAttributes(&ref, kLSRolesAll, attrNames, &values) == noErr ) {
CFTypeRef uti = CFDictionaryGetValue(values, kLSItemContentType);
CFStringRef extInfo = CFDictionaryGetValue(values, kLSItemExtension);
CFStringRef appInfo = CFDictionaryGetValue(values, kLSItemRoleHandlerDisplayName);
NSLog ( @"%@ -> %@ -> %@", uti, extInfo, appInfo );
prefferdMIMEType = UTTypeCopyPreferredTagWithClass( uti, kUTTagClassMIMEType );
}
if ( prefferdMIMEType == nil ) {
/* Your Own Codes */
}
return (NSString *)prefferdMIMEType;
}
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7. 2014/2/23
Cocoa
#23
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8. 2014/2/23
Cocoa
#23
struct LSItemInfoRecord {
LSItemInfoFlags flags; //調べた項目に対するフラグ情報。ビットごとに意味があるが調べるには以下の表の定義定数を使う
OSType filetype;
//ファイルタイプ
OSType creator;
//クリエイタ
CFStringRef extension; //ファイルの拡張子を示すCFStringへの参照（使用後のリリース必要）
CFStringRef iconFileName; //（未使用）
LSKindID kindID;
//（未使用）
};
typedef struct LSItemInfoRecord LSItemInfoRecord;
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9. 2014/2/23
Cocoa
#23
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