首先下載Realm源代碼，https://realm.io/cn/docs/objc/latest
將下載的文件解壓，從 ios/static/ 目錄中將 Realm.framework 拖曳到 Xcode 工程的文件導航器內，然后在 Xcode 文件導航器中選中工程。然后選擇應用目標，前往 Build Phases 選項卡。在 Link Binary with Libraries 部分中單擊 + 按鈕，然后添加 libc++.tbd 和 libz.tbd。這樣還沒有完，我們還需要安裝插件，打開解壓文件夾下的plugin，運行RealmPlugin.xcodeproj，然后重啟XCode。
這樣環境配置就完了，現在說重點如何去使用。
1.創建實體類
new File翻到最下面點擊創建Realm實體類
#import <Realm/Realm.h>@interface TestBean : RLMObject@property NSString* name;@property NSInteger age;@end// This protocol enables typed collections. i.e.:// RLMArray<TestBean *><TestBean>RLM_ARRAY_TYPE(TestBean)#import "TestBean.h"@implementation TestBean@end
2.增刪改查
這個增加，可以看到直接添加實體類就行了，這個RLMRealm就是數據庫的操作類，以后所有操作都靠他。
-(void)addAction{ NSLog(@"add"); self.name = _tf_name.text; self.age = [_tf_age.text integerValue]; TestBean* bean = [[TestBean alloc]init]; bean.name = self.name; bean.age = self.age; RLMRealm *realm = [RLMRealm defaultRealm]; [realm transactionWithBlock:^{ [realm addObject:bean]; }];}刪除也是通過刪除實體類來實現，但是我們需要首先通過查詢出實體類才行。這個查詢我們可以看到通過我們創建的實體類就能實現
-(void)deleteAction{ NSLog(@"delete"); RLMResults *dogs = [TestBean allObjects]; RLMRealm *realm = [RLMRealm defaultRealm]; [realm transactionWithBlock:^{ for (TestBean *bean in dogs) { [realm deleteObject:bean]; } }];}更新也是通過改變實體類的數據來實現
-(void)updateAction{ NSLog(@"update"); RLMResults *dogs = [TestBean allObjects]; [[RLMRealm defaultRealm] transactionWithBlock:^{ for (TestBean *bean in dogs) { bean.name = @"李四"; } }];}查詢我們還可以添加條件
// 使用斷言字符串來查詢RLMResults<Dog *> *tanDogs = [Dog objectsWhere:@"color = 'tan' AND name BEGINSWITH 'B'"];// 使用 NSPredicate 來查詢NSPredicate *pred = [NSPredicate predicateWithFormat:@"color = %@ AND name BEGINSWITH %@", @"tan", @"B"];tanDogs = [Dog objectsWithPredicate:pred];
3.排序
這個是在查詢完后去實現，通過實體類的key來排序。
-(void)sortAction{ NSLog(@"query"); RLMResults *dogs = [[TestBean allObjects] sortedResultsUsingKeyPath:@"name" ascending:YES]; [[RLMRealm defaultRealm] transactionWithBlock:^{ for (TestBean *bean in dogs) { NSLog(@"%@",bean.name); } }];}4.小結
只說了常用的功能，貼上官方中文文檔供大家參考
https://realm.io/cn/docs/objc/latest
5.例子代碼
//// ViewController.m// BmobTest//// Created by shanreal-iOS on 2017/12/9.// Copyright © 2017年 shanreal.LongZhenHao. All rights reserved.//#import "ViewController.h"#import "TestBean.h"@interface ViewController ()@property(nonatomic,strong)UIButton* add;@property(nonatomic,strong)UIButton* delete;@property(nonatomic,strong)UIButton* update;@property(nonatomic,strong)UIButton* query;@property(nonatomic,strong)UIButton* sort;@property(nonatomic,strong)NSString* name;@property(nonatomic,assign)NSInteger* age;@property(nonatomic,strong)UITextField* tf_name;@property(nonatomic,strong)UITextField* tf_age;@end@implementation ViewController- (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. _add = [[UIButton alloc]initWithFrame:CGRectMake(10, 30, 100, 20)]; [_add setTitle:@"add" forState:UIControlStateNormal]; [_add setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; [_add addTarget:self action:@selector(addAction) forControlEvents:UIControlEventTouchUpInside]; _delete = [[UIButton alloc]initWithFrame:CGRectMake(10, 60, 100, 20)]; [_delete setTitle:@"delete" forState:UIControlStateNormal]; [_delete setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; [_delete addTarget:self action:@selector(deleteAction) forControlEvents:UIControlEventTouchUpInside]; _update = [[UIButton alloc]initWithFrame:CGRectMake(10, 90, 100, 20)]; [_update setTitle:@"update" forState:UIControlStateNormal]; [_update setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; [_update addTarget:self action:@selector(updateAction) forControlEvents:UIControlEventTouchUpInside]; _query = [[UIButton alloc]initWithFrame:CGRectMake(10, 120, 100, 20)]; [_query setTitle:@"query" forState:UIControlStateNormal]; [_query setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; [_query addTarget:self action:@selector(queryAction) forControlEvents:UIControlEventTouchUpInside]; _sort = [[UIButton alloc]initWithFrame:CGRectMake(10, 150, 100, 20)]; [_sort setTitle:@"sort" forState:UIControlStateNormal]; [_sort setTitleColor:[UIColor blackColor] forState:UIControlStateNormal]; [_sort addTarget:self action:@selector(sortAction) forControlEvents:UIControlEventTouchUpInside]; _tf_name = [[UITextField alloc]initWithFrame:CGRectMake(50, 300, 200, 20)]; _tf_name.placeholder=@"name"; _tf_age = [[UITextField alloc]initWithFrame:CGRectMake(50, 350, 200, 20)]; _tf_age.placeholder=@"age"; [self.view addSubview:_add]; [self.view addSubview:_delete]; [self.view addSubview:_update]; [self.view addSubview:_query]; [self.view addSubview:_sort]; [self.view addSubview:_tf_name]; [self.view addSubview:_tf_age];}-(void)addAction{ NSLog(@"add"); self.name = _tf_name.text; self.age = [_tf_age.text integerValue]; TestBean* bean = [[TestBean alloc]init]; bean.name = self.name; bean.age = self.age; RLMRealm *realm = [RLMRealm defaultRealm]; [realm transactionWithBlock:^{ [realm addObject:bean]; }];}-(void)deleteAction{ NSLog(@"delete"); RLMResults *dogs = [TestBean allObjects]; RLMRealm *realm = [RLMRealm defaultRealm]; [realm transactionWithBlock:^{ for (TestBean *bean in dogs) { [realm deleteObject:bean]; } }];}-(void)updateAction{ NSLog(@"update"); RLMResults *dogs = [TestBean allObjects]; [[RLMRealm defaultRealm] transactionWithBlock:^{ for (TestBean *bean in dogs) { bean.name = @"李四"; } }];}-(void)queryAction{ NSLog(@"query"); RLMResults *dogs = [TestBean allObjects]; [[RLMRealm defaultRealm] transactionWithBlock:^{ for (TestBean *bean in dogs) { NSLog(@"%@",bean.name); } }];}-(void)sortAction{ NSLog(@"query"); RLMResults *dogs = [[TestBean allObjects] sortedResultsUsingKeyPath:@"name" ascending:YES]; [[RLMRealm defaultRealm] transactionWithBlock:^{ for (TestBean *bean in dogs) { NSLog(@"%@",bean.name); } }];}- (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated.}@end以上這篇基于iOS Realm數據庫的使用實例詳解就是小編分享給大家的全部內容了，希望能給大家一個參考，也希望大家多多支持VEVB武林網。
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