歡迎你們關注個人公衆號,我會按期分享一些我在項目中遇到問題的解決辦法和一些iOS實用的技巧,現階段主要是整理出一些基礎的知識記錄下來
git
文章也會同步更新到個人博客:
ppsheep.comgithub
sqlite幾乎在每一個APP編碼都會涉及到,它是一種輕量級的數據庫,在手機端使用起來極其方便,由於SQLite原生的接口都是使用C寫的,不是特別友好,全部有一個強大庫就出現了FMDB,今天咱們基於FMDB來進行二次封裝sql
首先來看一下個人項目結構數據庫
數據層的基本封裝思路是:數組
數據庫管理類的實現代碼:ui
#import#import "FMDB.h" @interface PPSDBManager : NSObject /** * DB隊列 還能夠定義其餘的數據庫 這裏只是一個示例 */ @property (nonatomic, strong) FMDatabaseQueue *commonQueue; + (PPSDBManager *)sharedInstance; /** 建立數據庫文件 @param userId 傳入用戶id @return 數據庫文件地址 */ + (NSString *)dbPath:(NSString *)userId; @end 複製代碼
這裏加入了用戶思想,即每一個用戶是一個數據庫文件,這樣好區分,並且每一個用戶能夠擁有不一樣的數據庫文件,這裏只建立了一個,固然還能夠建立不少個編碼
#import "PPSDBManager.h"
static PPSDBManager *manager;
@implementation PPSDBManager
+(PPSDBManager *)sharedInstance{
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
NSString *userID = @"ppsheep";//隨便寫了一個id
manager = [[PPSDBManager alloc] initWithUserId:userID];
});
return manager;
}
/**
通常的,若是有用戶的APP,這裏就能夠傳入當前用戶的id 用以區分數據庫
這裏我就隨便寫了
@param userId 用戶id
@return 實例
*/
- (instancetype)initWithUserId:(NSString *)userId{
if (self = [super init]) {
NSString *commonQueuePath = [PPSDBManager dbPath:userId];
self.commonQueue = [FMDatabaseQueue databaseQueueWithPath:commonQueuePath];
}
return self;
}
/**
數據庫文件地址
@return 地址
*/
+ (NSString *)dbPath: (NSString *)userId{
NSString *path = [NSString stringWithFormat:@"%@/User/%@/Setting/DB/", NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0], userId];
if (![[NSFileManager defaultManager] fileExistsAtPath:path]) {
//建立數據庫文件
NSError *error;
[[NSFileManager defaultManager] createDirectoryAtPath:path withIntermediateDirectories:YES attributes:nil error:&error];
if (error) {
NSLog(@"建立數據庫文件失敗:%@",path);
}
}
return [path stringByAppendingString:@"common.sqlite3"];
}
@end複製代碼
BaseStoreatom
#import#import "PPSDBManager.h" @interface PPSDBBaseStore : NSObject // 數據庫操做隊列(從NADBManager中獲取,默認使用commonQueue) @property (nonatomic, weak) FMDatabaseQueue *dbQueue; /** * 表建立 */ - (BOOL)createTable:(NSString*)tableName withSQL:(NSString*)sqlString; /* * 執行帶數組參數的sql語句 (增,刪,改) */ -(BOOL)excuteSQL:(NSString*)sqlString withArrParameter:(NSArray*)arrParameter; /* * 執行帶字典參數的sql語句 (增,刪,改) */ -(BOOL)excuteSQL:(NSString*)sqlString withDicParameter:(NSDictionary*)dicParameter; /* * 執行格式化的sql語句 (增,刪,改) */ - (BOOL)excuteSQL:(NSString *)sqlString,...; /** * 執行查詢指令 */ - (void)excuteQuerySQL:(NSString*)sqlStr resultBlock:(void (^)(FMResultSet * rsSet))resultBlock; @end 複製代碼
Base定義的一些基礎的操做,註釋都寫的很清楚,我就不一一解釋了spa
//查詢語句
- (BOOL)excuteSQL:(NSString *)sqlString,...
{
__block BOOL ok = NO;
if (self.dbQueue) {
va_list args;
va_list *p_args;
p_args = &args;
va_start(args, sqlString);
[self.dbQueue inDatabase:^(FMDatabase *db) {
ok = [db executeUpdate:sqlString withVAList:*p_args];
}];
va_end(args);
}
return ok;
}複製代碼
帶參數的查詢方法:code
- (BOOL)excuteSQL:(NSString *)sqlString withArrParameter:(NSArray *)arrParameter
{
__block BOOL ok = NO;
if (self.dbQueue) {
[self.dbQueue inDatabase:^(FMDatabase *db) {
ok = [db executeUpdate:sqlString withArgumentsInArray:arrParameter];
}];
}
return ok;
}複製代碼
Base裏面的方法,都是調用FMDB
如今,咱們有一個User模塊,須要實現用戶的存取,首先,咱們須要一個裝SQL的文件,分離SQL
PPSDBUserSQL.h
#ifndef PPSDBUserSQL_h
#define PPSDBUserSQL_h
#define USER_TABLE_NAME @"user"
/**
* 建表
*
* @param uid 當前用戶Corp郵箱前綴
* @param fid 好友Corp郵箱前綴
* @param email Corp郵箱
*
* @return
*/
#define SQL_CREATE_USER_TABLE
@"CREATE TABLE IF NOT EXISTS %@(\
uid TEXT,\
name TEXT,\
email TEXT,\
phoneNum TEXT,\
ext1 TEXT,\
ext2 TEXT,\
ext3 TEXT,\
ext4 INTEGER DEFAULT (0),\
ext5 INTEGER DEFAULT (0),\
ext6 INTEGER DEFAULT (0),\
PRIMARY KEY(uid))"
#define SQL_ADD_USER @"INSERT OR REPLACE INTO %@ ( uid, name, email, phoneNum, ext1, ext2, ext3, ext4, ext5, ext6) VALUES ( ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)"
#define SQL_SELECT_USER @"SELECT * FROM %@ WHERE uid = '%@'"
#define SQL_GET_ALL_USER @"SELECT * FROM %@ "
#define SQL_DELETE_USER @"DELETE FROM %@ WHERE uid = '%@'"
#define SQL_UPDATE_USER @"UPDATE %@ SET name = ?, email = ?, phoneNum = ? WHERE uid = '%@' "
#endif /* PPSDBUserSQL_h */複製代碼
而後是具體的操做User的Store 包含了基本的
#import "PPSDBBaseStore.h"
@class PPSUser;
@interface PPSDBUserStore : PPSDBBaseStore
//改
- (BOOL)updateUserData:(NSArray *)users;
//增
- (BOOL)addUser:(NSArray *)users;
//查
- (NSMutableArray *)usersByUserIds:(NSArray *)userIds;
//刪
- (BOOL)deleteUserByUid:(NSArray *)userIds;
- (NSArray *)allUsers;
@end複製代碼
批量查詢用戶,傳入id數組
-(NSMutableArray *)usersByUserIds:(NSArray *)userIds{
NSArray *ids = [userIds copy];
__block NSMutableArray *data = [[NSMutableArray alloc] init];
for (NSString *userId in ids) {
NSString *sqlString = [NSString stringWithFormat:SQL_SELECT_USER, USER_TABLE_NAME, userId];
[self excuteQuerySQL:sqlString resultBlock:^(FMResultSet *retSet) {
while ([retSet next]) {
NSDictionary *dic = @{
@"userId" : [retSet stringForColumn:@"uid"],
@"email" : [retSet stringForColumn:@"email"],
@"name" : [retSet stringForColumn:@"name"],
@"phoneNum" : [retSet stringForColumn:@"phoneNum"],
};
PPSUser *user = [[PPSUser alloc] initWithDic:dic];
[data addObject:user];
}
[retSet close];
}];
}
return data;
}複製代碼
批量更新用戶,傳入用戶數組
-(BOOL)updateUserData:(NSArray *)users{
NSArray *userCopy = [users copy];
BOOL ok = YES;
for (PPSUser *user in userCopy) {
NSString *sql = [NSString stringWithFormat:SQL_UPDATE_USER, USER_TABLE_NAME, user.userId];
NSArray *arrPara = [NSArray arrayWithObjects:
PPSNoNilString(user.name),
PPSNoNilString(user.email),
PPSNoNilString(user.phoneNum),
@"", @"", @"", @0, @0, @0, nil];
ok = [self excuteSQL:sql withArrParameter:arrPara];
}
return ok;
}複製代碼
爲了方便,我就直接在ViewController中寫了,在真正的開發中,通常都會在管理類中進行數據庫操做
懶加載一個用戶數據庫
-(PPSDBUserStore *)store{
if (!_store) {
_store = [[PPSDBUserStore alloc] init];
}
return _store;
}複製代碼
初始化用戶,直接插入
- (void)initUsers{
NSMutableArray *arr = [NSMutableArray array];
for (int i=0; i<10; i++)="" {="" ppsuser="" *user="[[PPSUser" alloc]="" init];="" user.userid="[NSString" stringwithformat:@"%ld_userid",(long)i];="" user.name="[NSString" stringwithformat:@"%ld_username",(long)i];="" user.email="[NSString" stringwithformat:@"%ld_email",(long)i];="" user.phonenum="[NSString" stringwithformat:@"%ld_phonenum",(long)i];="" [arr="" addobject:user];="" }="" [self.store="" adduser:arr];="" }<="" code="">
複製代碼
我就再也不貼代碼出來了,項目工程,我放在了