iOS中 学会如何对sqlite3 进行封装

#waring ---(看官注意) ---使用说明:

①在创建自定义model类之前让该类继承自文件中的Model类,

②为model类选一个NSString属性作为主键:(既,在初始化方法里面将从父类Model类

ID属性等于你所选的NSString属性值即可 (具体可参见.下文  二.3 中)

　　

　　　　

一.文件夹结构:

二.文件说明:

1.NSObject+NSCoding

　　该文件是对对象类型进行encoding 以及 decoding操作的方法

2.DataHandle

　　　　 1.　该文件是 sqlite3 单例数据库对Model 对象进行增.删.查.改

　　

　 3.Model文件夹下面的Model 是遵守NSCoding 协议的底层Model

　　 　　1. 而Model文件夹下面的TestModel 则是继承自Model 的一种自定义model (也就是我们项目中的自定义的Model),

　　　　 2.如此,我们自己项目中的自定义model 只要继承字Model 类就可以了,

　　　　 3.但还要在自定义的TestModel中添加以下改动: self.ID属性是从父类Model中继承来的 而Model 的ID属性被设置为数据库的主键, 因此不可以为空,需要将TestModel的一个属性替代ID属性,既作为主键;

三.各个文件的代码示例

　1.NSObject+NSCoding

.h文件

　　.m文件

#import "NSObject+NSCoding.h"
#import <objc/runtime.h>
#import <UIKit/UIKit.h>

@implementation NSObject (NSCoding)

- (NSMutableDictionary *)propertiesForClass:(Class)klass {
    
    NSMutableDictionary *results = [[NSMutableDictionary alloc] init];
    
    unsigned int outCount, i;
    //通过运行时获取 该类所有属性列表
    objc_property_t *properties = class_copyPropertyList(klass, &outCount);
    for(i = 0; i < outCount; i++) {
        objc_property_t property = properties[i];
        
        NSString *pname = [NSString stringWithCString:property_getName(property) encoding:NSUTF8StringEncoding];
        NSString *pattrs = [NSString stringWithCString:property_getAttributes(property) encoding:NSUTF8StringEncoding];
        
        pattrs = [[pattrs componentsSeparatedByString:@","] objectAtIndex:0];
        pattrs = [pattrs substringFromIndex:1];
        
        [results setObject:pattrs forKey:pname];
    }
    free(properties);
    
    if ([klass superclass] != [NSObject class]) {
        [results addEntriesFromDictionary:[self propertiesForClass:[klass superclass]]];
    }
    
    return results;
}

- (NSDictionary *)properties {
    return [self propertiesForClass:[self class]];
}

- (void)autoEncodeWithCoder:(NSCoder *)coder {
    NSDictionary *properties = [self properties];
    for (NSString *key in properties) {
        NSString *type = [properties objectForKey:key];
        id value;
        unsigned long long ullValue;
        BOOL boolValue;
        float floatValue;
        double doubleValue;
        NSInteger intValue;
        unsigned long ulValue;
        long longValue;
        unsigned unsignedValue;
        short shortValue;
        NSString *className;
        
        NSMethodSignature *signature = [self methodSignatureForSelector:NSSelectorFromString(key)];
        NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:signature];
        [invocation setSelector:NSSelectorFromString(key)];
        [invocation setTarget:self];
        
        switch ([type characterAtIndex:0]){
            case '@':   // object
                if ([[type componentsSeparatedByString:@"\""] count] > 1) {
                    className = [[type componentsSeparatedByString:@"\""] objectAtIndex:1];
                    Class class = NSClassFromString(className);
                    
#warning UIImage类型的属性不归档  add by yhy›
                    if ([className isEqualToString:@"UIImage"]) {
                        //如果属性是UIImage类型的，不进行归档
                        break;
                    }
                    
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
                    value = [self performSelector:NSSelectorFromString(key)];
#pragma clang diagnostic pop
                    
                    // only decode if the property conforms to NSCoding
                    if([class conformsToProtocol:@protocol(NSCoding)]){
                        [coder encodeObject:value forKey:key];
                    }
                }
                break;
            case 'c':   // bool
                [invocation invoke];
                [invocation getReturnValue:&boolValue];
                [coder encodeObject:[NSNumber numberWithBool:boolValue] forKey:key];
                break;
            case 'f':   // float
                [invocation invoke];
                [invocation getReturnValue:&floatValue];
                [coder encodeObject:[NSNumber numberWithFloat:floatValue] forKey:key];
                break;
            case 'd':   // double
                [invocation invoke];
                [invocation getReturnValue:&doubleValue];
                [coder encodeObject:[NSNumber numberWithDouble:doubleValue] forKey:key];
                break;
            case 'i':   // int
                [invocation invoke];
                [invocation getReturnValue:&intValue];
                [coder encodeObject:[NSNumber numberWithInt:(int)intValue] forKey:key];
                break;
            case 'L':   // unsigned long
                [invocation invoke];
                [invocation getReturnValue:&ulValue];
                [coder encodeObject:[NSNumber numberWithUnsignedLong:ulValue] forKey:key];
                break;
            case 'Q':   // unsigned long long
                [invocation invoke];
                [invocation getReturnValue:&ullValue];
                [coder encodeObject:[NSNumber numberWithUnsignedLongLong:ullValue] forKey:key];
                break;
            case 'l':   // long
                [invocation invoke];
                [invocation getReturnValue:&longValue];
                [coder encodeObject:[NSNumber numberWithLong:longValue] forKey:key];
                break;
            case 's':   // short
                [invocation invoke];
                [invocation getReturnValue:&shortValue];
                [coder encodeObject:[NSNumber numberWithShort:shortValue] forKey:key];
                break;
            case 'I':   // unsigned
                [invocation invoke];
                [invocation getReturnValue:&unsignedValue];
                [coder encodeObject:[NSNumber numberWithUnsignedInt:unsignedValue] forKey:key];
                break;
            default:
                break;
        }
    }
}

- (void)autoDecode:(NSCoder *)coder {
    NSDictionary *properties = [self properties];
    for (NSString *key in properties) {
        NSString *type = [properties objectForKey:key];
        id value;
        NSNumber *number;
        NSInteger i;
        CGFloat f;
        BOOL b;
        double d;
        unsigned long ul;
        unsigned long long ull;
        long longValue;
        unsigned unsignedValue;
        short shortValue;
        
        NSString *className;
        
        switch ([type characterAtIndex:0]) {
            case '@':   // object
                if ([[type componentsSeparatedByString:@"\""] count] > 1) {
                    className = [[type componentsSeparatedByString:@"\""] objectAtIndex:1];
                    Class class = NSClassFromString(className);
                    
#warning UIImage类型的属性不归档  add by yhy
                    if ([className isEqualToString:@"UIImage"]) {
                        //如果属性是UIImage类型的，不进行反归档
                        break;
                    }

// only decode if the property conforms to NSCoding
                    if ([class conformsToProtocol:@protocol(NSCoding )]){
                        value = [coder decodeObjectForKey:key];
                        [self setValue:value forKey:key];
                    }
                }
                break;
            case 'c':   // bool
                number = [coder decodeObjectForKey:key];
                b = [number boolValue];
                [self setValue:@(b) forKey:key];
                break;
            case 'f':   // float
                number = [coder decodeObjectForKey:key];
                f = [number floatValue];
                [self setValue:@(f) forKey:key];
                break;
            case 'd':   // double
                number = [coder decodeObjectForKey:key];
                d = [number doubleValue];
                [self setValue:@(d) forKey:key];
                break;
            case 'i':   // int
                number = [coder decodeObjectForKey:key];
                i = [number intValue];
                [self setValue:@(i) forKey:key];
                break;
            case 'L':   // unsigned long
                number = [coder decodeObjectForKey:key];
                ul = [number unsignedLongValue];
                [self setValue:@(ul) forKey:key];
                break;
            case 'Q':   // unsigned long long
                number = [coder decodeObjectForKey:key];
                ull = [number unsignedLongLongValue];
                [self setValue:@(ull) forKey:key];
                break;
            case 'l':   // long
                number = [coder decodeObjectForKey:key];
                longValue = [number longValue];
                [self setValue:@(longValue) forKey:key];
                break;
            case 'I':   // unsigned
                number = [coder decodeObjectForKey:key];
                unsignedValue = [number unsignedIntValue];
                [self setValue:@(unsignedValue) forKey:key];
                break;
            case 's':   // short
                number = [coder decodeObjectForKey:key];
                shortValue = [number shortValue];
                [self setValue:@(shortValue) forKey:key];
                break;
            default:
                break;
        }
    }
}

@end

2.DataHandle文件

　　　　　　.h文件

　　　　.m文件

　　　　　　#import <sqlite3.h>
#import "DatabaseHandle.h"
#import "Model.h"
#define ARCHIVERKEY @"archiver"
static DatabaseHandle *dataHandle =nil;

@implementation DatabaseHandle
+ (DatabaseHandle*)shardInstnce{
    @synchronized(self){
        if (dataHandle == nil) {
            dataHandle = [[DatabaseHandle alloc]init];
            
        }
        return dataHandle;
    }
}

//打开数据库

static sqlite3 *db = nil;
- (void)openDB{
    
    if (db !=nil) {
        return;
    }
    
    NSString *filePath = [self useCachesPathSqlite:@"WatchBall.sqlite"];
    NSLog(@"db filePath = %@",filePath);
    
    int result = sqlite3_open(filePath.UTF8String, &db);
    if (result ==SQLITE_OK) {
        NSString *createModelSql = @"CREATE TABLE ModelList(ID TEXT PRIMARY KEY,title TEXT,imageUrl TEXT,data BLOB)";
        //执行参数?
        sqlite3_exec(db, [createModelSql UTF8String], NULL, NULL, NULL);
    }
}
- (void)closeDB{
    int result = sqlite3_close(db);
    if (result ==SQLITE_OK) {
        db = nil;
        NSLog(@"关闭成功");
    }
}
//插入收藏活动

- (void)insertNewactivity:(Model *)model{
    [self openDB];
    static sqlite3_stmt *stmt = nil;
    NSString *sql = @"insert into ModelList(ID,title,imageUrl,data) values (?,?,?,?)";
    int result = sqlite3_prepare_v2(db, sql.UTF8String, -1, &stmt, nil);
    
    if (result ==SQLITE_OK) {
        sqlite3_bind_text(stmt, 1, [model.ID UTF8String], -1, nil);
        sqlite3_bind_text(stmt, 2, [model.title UTF8String], -1, nil);
        sqlite3_bind_text(stmt, 3, [model.imageUrl UTF8String], -1, nil);
        
        NSString *archiverKey = [NSString stringWithFormat:@"%@%@",ARCHIVERKEY,model.ID];
        NSData *data = [self dataOfArchiverObject:model forKey:archiverKey];
        sqlite3_bind_blob(stmt, 4, [data bytes], (int)[data length], nil);
        
        sqlite3_step(stmt);
    }
    sqlite3_finalize(stmt);
}

- (void)deleteModelByID:(NSString *)ID{
    
    [self openDB];
    
    NSString *deleteSQL = [NSString stringWithFormat:@"delete from ModelList where ID ='%@'",ID];
    
    char * error =nil;
    
    int result = sqlite3_exec(db, deleteSQL.UTF8String, NULL, NULL, &error);
    
    if (result == SQLITE_OK) {
        
        NSLog(@"删除成功");
        
    }else{
        
        NSLog(@"删除失败 error = %s",error);
        
    }
 
    
}

- (Model*)selectModelWithID:(NSString *)ID{
    [self openDB];
    
    sqlite3_stmt *stmt = nil;
    
    NSString *sql = @"select data from ModelList where ID = ?";
    
    int result = sqlite3_prepare_v2(db, [sql UTF8String], -1, &stmt, NULL);
    
    Model *model = nil;
    
    if (result ==SQLITE_OK) {
        sqlite3_bind_text(stmt, 1, [ID UTF8String], -1, NULL);
        if (sqlite3_step(stmt) ==SQLITE_ROW) {
            
            
            NSData *data = [NSData dataWithBytes:sqlite3_column_blob(stmt, 0) length:sqlite3_column_bytes(stmt, 0)];
            
            NSString *archiver = [NSString stringWithFormat:@"%@%@",ARCHIVERKEY,ID];
            model = [self unarchiverObject:data forKey:archiver];
 
        }
    }
    sqlite3_finalize(stmt);
    return model;
    
}

- (NSArray*)selectAllModel{
    [self openDB];
    
    sqlite3_stmt *stmt = nil;
    NSString *sql = @"select ID,data from ModelList";
    
    int result = sqlite3_prepare_v2(db, [sql UTF8String], -1, &stmt, NULL);
    
    NSMutableArray *activityArray = [NSMutableArray array];
    
    
    if (result == SQLITE_OK) {
        
        while (sqlite3_step(stmt) ==SQLITE_ROW) {
            NSString *ID = [NSString stringWithUTF8String:(const char*)sqlite3_column_text(stmt, 0)];
            NSData *data = [NSData dataWithBytes:sqlite3_column_blob(stmt, 1) length:sqlite3_column_bytes(stmt, 1)];
            NSString *modelKey = [NSString stringWithFormat:@"%@%@",ARCHIVERKEY,ID];
            
            Model * model = [self unarchiverObject:data forKey:modelKey];
            [activityArray addObject:model];
            NSLog(@"%@",model);
            
        }
    }
    sqlite3_finalize(stmt);
    
    if (activityArray.count ==0) {
        return nil;
    }
    return activityArray;
}

- (BOOL)isFavoriteModelWithID:(NSString *)ID{
    
    Model *model = [self selectModelWithID:ID];
    if (model ==nil) {
        NSLog(@"没有收藏该条目");
        return NO;
        
    }
    NSLog(@"已经收藏");
    return YES;
    
}

#pragma ---文件路径处理----
////文件夹路径处理
- (NSString*)useCachesPathSqlite:(NSString*)databaseName{
    
    NSString *caches = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES).lastObject;
    
    NSString *filePath = [caches stringByAppendingPathComponent:databaseName];
    return filePath;
}
#pragma ---归档处理---
- (NSData *)dataOfArchiverObject:(id)object forKey:(NSString*)key{
    NSMutableData *data = [NSMutableData data];
    
    NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc]initForWritingWithMutableData:data];
    [archiver encodeObject:object forKey:key];
    [archiver finishEncoding];
    return data;
    
}

- (id)unarchiverObject:(NSData*)data forKey:(NSString *)key{
    NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc]initForReadingWithData:data];
    
    id object = [unarchiver decodeObjectForKey:key];
    [unarchiver finishDecoding];
    
    return object;
}

@end

　　3.基类Model

　　　　　　.h文件

　　

　　　　　　.m文件