深入理解iPhone数据持久化(手把手教你iphone开发 – 基础篇)

- (void)applicationDidFinishLaunching:(UIApplication *)application { 
 NSString *strOne = @"Persistent data1";
 NSString *strTwo = @"Persistent data 2";
 
 NSMutableArray *persistentArray = [[NSMutableArray alloc] init];
 [persistentArray addObject:strOne];
 [persistentArray addObject:strTwo];
 
 //archive
 NSUserDefaults *persistentDefaults = [NSUserDefaults standardUserDefaults];
 [persistentDefaults setObject:persistentArray forKey:@"myDefault"];
 NSString *descriptionDefault = [persistentDefaults description];
 NSLog(@"NSUserDefaults description is :%@",descriptionDefault);
 
 //unarchive
 NSArray *UnpersistentArray =
[persistentDefaults objectForKey:@"myDefault"];
 
 NSString *UnstrOne = [UnpersistentArray objectAtIndex:0];
 NSString *UnstrTwo = [UnpersistentArray objectAtIndex:1];
 
 NSLog(@"UnstrOne = %@,UnstrTwo = %@",UnstrOne,UnstrTwo);
 
 // Override point for customization after application launch
 [window makeKeyAndVisible];
}

- (void)applicationDidFinishLaunching:(UIApplication *)application { 
 NSString *strOne = @"Persistent data1";
 NSString *strTwo = @"Persistent data 2";
 
 NSArray *persistentArray = [NSArray arrayWithObjects:strOne,strTwo,nil];
 NSArray *pathArray = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,    NSAllDomainsMask, YES);
 
 int pathLen = [pathArray count];
 
 NSLog(@"path number is :%d",pathLen);
 
 NSString *filePath;
 
 for(int i = 0; i < pathLen; i++)
 {
  filePath = [pathArray objectAtIndex:i];
  NSLog(@"%d path is :%@",i,filePath);
 }
 
 NSString *myFilename = [filePath stringByAppendingPathComponent:@"myFile.rtf"];
 
 NSLog(@"myfile‘s path is :%@",myFilename);
 
 // no files generated in correspond directory now
 
 [NSKeyedArchiver archiveRootObject:persistentArray toFile:myFilename];
 // now the myFile.rtf is generated
 
 // Override point for customization after application launch
 [window makeKeyAndVisible];
}

(void)applicationDidFinishLaunching:(UIApplication *)application { 
 NSString *myFilename;
 // archive
 {
  NSString *strOne = @"Persistent data1";
  NSString *strTwo = @"Persistent data 2";
 
  NSMutableArray *persistentArray = [[NSMutableArray alloc] init];
  [persistentArray addObject:strOne];
  [persistentArray addObject:strTwo];
 
  NSArray *pathArray = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,    NSAllDomainsMask, YES);
 
  int pathLen = [pathArray count];
  NSLog(@"path number is :%d",pathLen);
 
  NSString *filePath;
 
  for(int i = 0; i < pathLen; i++)
  {
   filePath = [pathArray objectAtIndex:i];
 
   NSLog(@"%d path is :%@",i,filePath);
  }
 
  myFilename = [filePath stringByAppendingPathComponent:@"myFile.rtf"];
 
  NSLog(@"myfile‘s path is :%@",myFilename);
 
  [NSKeyedArchiver archiveRootObject:persistentArray toFile:myFilename];
 }
 
 // unarchive
 {
  NSArray *unarchiveArray = [NSKeyedUnarchiver unarchiveObjectWithFile:myFilename];
  NSString *UnstrOne = [unarchiveArray objectAtIndex:0];
  NSString *UnstrTwo = [unarchiveArray objectAtIndex:1];
 
  NSLog(@"UnstrOne = %@,UnstrTwo = %@",UnstrOne,UnstrTwo);
 }
 
 
 // Override point for customization after application launch
 [window makeKeyAndVisible];
}

#import <UIKit/UIKit.h>
 
#include "sqlite3.h"
#define kFileName @"mydb.sql"
 
@interface PersistentExampleAppDelegate : NSObject <UIApplicationDelegate> {
 sqlite3 *database;
 UIWindow *window;
}
 
@property (nonatomic, retain) IBOutlet UIWindow *window;
 
@end

(void)applicationDidFinishLaunching:(UIApplication *)application { 
 
 NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
 NSString *paths = [[path objectAtIndex:0] stringByAppendingPathComponent:kFileName];
 
 NSFileManager *fileManager = [NSFileManager defaultManager];
 BOOL findFile = [fileManager fileExistsAtPath:paths];
 
 NSLog(@"Database file path = %@",paths);
 
 // 如果找到了数据库文件
 if(findFile)
 {
  NSLog(@"Database file have already existed.");
 
  if(sqlite3_open([paths UTF8String], &database) != SQLITE_OK)//打开数据库失败
  {
   sqlite3_close(database);
   NSAssert(0,@"Failed to open database");
  }
 }else
 {
  NSLog(@"Database file does not exsit!");
  if(sqlite3_open([paths UTF8String], &database) != SQLITE_OK)//打开数据库失败
  {
   sqlite3_close(database);
   NSAssert(0,@"Failed to open database");
  }
 }
 
 char *errorMsg;
 
//创建表
 NSString *createSQL = @"create table if not exists fields (row integer primary key, field_data text);"; 
 if(sqlite3_exec(database, [createSQL UTF8String],NULL,NULL,&errorMsg)!=SQLITE_OK)
 {
  sqlite3_close(database);
  NSAssert1(0,@"Error creating table: %s",errorMsg);
 }
 
 NSString *strOne = @"Persistent data1";
 NSString *strTwo = @"Persistent data 2";
 
 NSMutableArray *persistentArray = [[NSMutableArray alloc] init];
 [persistentArray addObject:strOne];
 [persistentArray addObject:strTwo];
 
 for (int i = 0; i < [persistentArray count]; i++) {
  NSString *upDataSQL = [[NSString alloc] initWithFormat:@"insert or replace into
fields (row,field_data) values (%d,‘%@‘);",i,[persistentArray objectAtIndex:i]];
 
  char* errorMsg;
  if(sqlite3_exec(database,[upDataSQL UTF8String],NULL,NULL,&errorMsg)
!= SQLITE_OK)
  {
   sqlite3_close(database);
   NSAssert(0,@"Failed to open database");
  }
 }
 
 //unarchive
 NSString *query = @"select row, field_data from fields order by row";//查找表中的数据 
 sqlite3_stmt *statement;
 if(sqlite3_prepare_v2(database, [query UTF8String], -1, &statement, nil)
== SQLITE_OK)
 {
  while(sqlite3_step(statement) == SQLITE_ROW)
  {
   int row = sqlite3_column_int(statement, 0);
   char *rowData = (char *)sqlite3_column_text(statement, 1);
 
   NSString *fieldName = [[NSString alloc] initWithFormat:@"show%d",row];
   NSString *fieldValue = [[NSString alloc] initWithUTF8String:rowData];
 
   NSLog(@"fieldName is :%@,fieldValue is :%@",fieldName,fieldValue);
 
   [fieldName release];
   [fieldValue release];
  }
  sqlite3_finalize(statement);
 }
 
 // Override point for customization after application launch
 [window makeKeyAndVisible];
}

 (void)applicationDidFinishLaunching:(UIApplication *)application { 
 
 NSString *strOne = @"Persistent data1";
 NSString *strTwo = @"Persistent data 2";
 
 NSMutableArray *persistentArray = [[NSMutableArray alloc] init];
 [persistentArray addObject:strOne];
 [persistentArray addObject:strTwo];
 
 
 
 NSArray *filePathArray = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
 NSString *filePath =
-          [[filePathArray objectAtIndex:0] stringByAppendingPathComponent:@"mydatas.plist"];
 
 [[NSArray arrayWithObjects:persistentArray,nil] writeToFile:filePath atomically:NO];
 
 //load
 NSMutableArray *saveDataArray = [[NSMutableArray alloc] init];
 if([[NSFileManager defaultManager] fileExistsAtPath:filePath])
  saveDataArray = [NSMutableArray arrayWithContentsOfFile:filePath];  
 else
  saveDataArray = [NSMutableArray arrayWithContentsOfFile:[[NSBundle
-                  mainBundle] pathForResource:@"Savedatas" ofType:@"plist"]];
-          
 NSArray *strArray = [saveDataArray objectAtIndex:0];
 
 NSString *UnstrOne = [strArray objectAtIndex:0];
 NSString *UnstrTwo = [strArray objectAtIndex:1];
 
 // Override point for customization after application launch
 [window makeKeyAndVisible];
}