Archive and archive

Archive and archive
1. Archiving

NSArray * array = @ [@ "ARCHIVE", @ "", @ ""];

// 1. Create an archive object

NSMutableData * data = [NSMutableDatadata];

NSKeyedArchiver * archiver = [[NSKeyedArchiveralloc] initForWritingWithMutableData: data];

// 2. Archive

[Archiver encodeObject: primary key: @ "array"];

// 3. the archive is terminated. If the archive is terminated, the archive is invalid.

[Archiver finishEncoding];

[Array release];

[Archiver release];

// 4. Obtain the path of the written file. No file is automatically created.
NSString * documentPath =
[NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
NSString * newFiel = [documentPathstringByAppendingPathComponent: @ "bb.txt"];

// 5. Write data to the file

BOOL isSucceed = [datawriteToFile: [selfgetFiel] atomically: YES];

Ii. Archive operations

// 1. initialize NSMutableData Based on the file path

NSMutableData * Data = [NSMutableDatadataWithContentsOfFile:/Users/lanouhn/Library/Application Support/iPhone Simulator/7.1/Applications/300BEFD5-1F93-47A3-A1B3-936195FAA53F];

// 2. Create an archive class

NSKeyedUnarchiver * unarchiver = [[NSKeyedUnarchiveralloc] initForReadingWithData: Data];

// 3. Archive

NSArray * array = [unarchiverdecodeObjectForKey: @ "array"];

// 4. End the archive

[Unarchiver finishDecoding];

[Unarchiver release];

3. Note

1. If you want to archive a class object, you must enable the class to implement the NSCoding protocol.

2. When the object is a string, array, Dictionary, or set, the semantic attribute of the attribute is declared as copy.

3. When assigning values to instance variables after defining attributes, use the setter method.

Example
@ Interface Person: NSObject
@ Property (nonatomic, copy) NSString * name