iOS Sqlite3數據庫簡明教程

1，導入支持sqlite3的本地frame: libsqlite3.tbd (Xcode 7及更高版本後綴爲 .tbd ，Xcode 6 及以前版本後綴爲 .dylib)

2,導入頭文件並設置所需屬性：

#import "ViewController.h"
#import "Person.h"
#import "sqlite3.h"

@interface ViewController ()

@property (nonatomic,assign) sqlite3 *sqlite3;
@property (nonatomic,strong) NSArray *dataList;

3，建立數據庫，若是要打開某個數據庫文件也用此方法，有此文件名會打開，沒有默認建立：

#pragma mark_Sqlite3Open
- (void)openDatabase {
    //1.設置文件名
    NSString *filename = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject stringByAppendingPathComponent:@"person.db"];
    //2.打開數據庫文件，若是沒有會自動建立一個文件
    NSInteger result = sqlite3_open(filename.UTF8String, &_sqlite3);
    if (result == SQLITE_OK) {
        NSLog(@"打開數據庫成功！");
        //3.建立一個數據庫表
        char *errmsg = NULL;
        sqlite3_exec(_sqlite3, "CREATE TABLE IF NOT EXISTS t_person(id integer primary key autoincrement, name text, age integer)", NULL, NULL, &errmsg);
        if (errmsg) {
            NSLog(@"錯誤：%s", errmsg);
        } else {
            NSLog(@"創表成功！");
        }
    } else {
        NSLog(@"打開數據庫失敗！");
    }
}

4，往數據庫中錄入數據：

#pragma mark_Sqlite3Insert
- (void)insertData {
    
    NSString *nameStr;
    NSInteger age;
    for (NSInteger i = 0; i < 1000; i++) {
        nameStr = [NSString stringWithFormat:@"Bourne-%d", arc4random_uniform(1000)];
        age = arc4random_uniform(80) + 20;
        NSString *sql = [NSString stringWithFormat:@"INSERT INTO t_person (name, age) VALUES('%@', '%ld')", nameStr, age];
        char *errmsg = NULL;
        sqlite3_exec(_sqlite3, sql.UTF8String, NULL, NULL, &errmsg);
        if (errmsg) {
            NSLog(@"錯誤：%s", errmsg);
        }
    }
    NSLog(@"插入完畢！");
}

5，讀取數據庫：

     5.1，建立一個Person類：

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>

@interface Person : NSObject<NSCoding>

//@property (nonatomic,strong) UIImage *img;
@property (nonatomic,copy) NSString *name;
@property (nonatomic,assign) NSInteger age;

+(in)personWithName:(NSString *)name Age:(NSInteger)age;

@end

     5.2，實現Person中的方法：

#import "Person.h"

@implementateion Person

+(instancetype)personWithName:(NSString *)name Age:(NSInteger)age{
    
    Person *person = [[Person alloc]init];
    person.name = name;
    person.age = age;

    return person;
    
}

@end

    5.3,讀取數據庫中的數據：

#pragma mark_Sqlite3Read
- (void)readData {
    
    //讀取數據庫中數據以前，須要先打開數據庫
    NSMutableArray *mArray = [NSMutableArray arrayWithCapacity:1000];
    char *sql = "select name, age from t_person;";
    sqlite3_stmt *stmt;
    NSInteger result = sqlite3_prepare_v2(_sqlite3, sql, -1, &stmt, NULL);
    
    if (result == SQLITE_OK) {
         NSLog(@"STMT:%d",sqlite3_step(stmt));
        while (sqlite3_step(stmt) == SQLITE_ROW) {
            char *name = (char *)sqlite3_column_text(stmt, 0);
            NSInteger age = sqlite3_column_int(stmt, 1);
            
            //建立對象
            
            Person *person = [Person personWithName:[NSString stringWithUTF8String:name] Age:age];
            
           //
            NSLog(@"Name:%@ Age:%ld PName:%@ Page:%ld",[NSString stringWithUTF8String:name],age,person.name,person.age);
            
            [mArray addObject:person];
        }
        self.dataList = mArray;
    }
    sqlite3_finalize(stmt);
    
    
    NSLog(@"DataList:%@",self.dataList);
}

注：讀數據庫時必定要先打開數據庫