iOS: 学习笔记, 使用FMDatabase操作sqlite3

使用FMDatabase操作sqlite3数据库非常简单和方便

 //
 //  main.m
 //  iOSDemo0602_sqlite3
 //
 //  Created by yao_yu on 14-6-2.
 //  Copyright (c) 2014年 yao_yu. All rights reserved.
 //

 #import <UIKit/UIKit.h>
 #import "FMDatabase.h"

 void test01();
 BOOL isfile(NSString *path);
 BOOL isdir(NSString *path);

 int main(int argc, char * argv[])
 {
     @autoreleasepool {
         test01();
     }
     return ;
 }

 void test01()
 {
     NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentationDirectory, NSUserDomainMask, YES);
     NSString *docpath = [paths objectAtIndex:];
     NSString *dbpath = [docpath stringByAppendingPathComponent:@"YY/Data2"];
 //    NSLog(@"%@", dbpath);
     if (!isdir(dbpath)) {
         NSFileManager *fileManager = [NSFileManager defaultManager];
         [fileManager createDirectoryAtPath:dbpath withIntermediateDirectories:YES attributes:nil error:nil];
     }

     NSString *dbfile = [dbpath stringByAppendingPathComponent:@"data.db"];
     NSLog(@"%@", dbfile);

     //初始化
     FMDatabase *db = [FMDatabase databaseWithPath:dbfile];
     //打开数据库
     [db open];

     //删除表
     [db executeUpdate:@"drop table persons"];

     //添加表
     [db executeUpdate:@"create table persons(id, name)"];

     //删除原有数据
     [db executeUpdate:@"delete from persons"];

     //使用事务添加数据
     [db beginTransaction];
     for(int i=; i< ; i++)
     {
         [db executeUpdate:@"insert into persons values(?,?)", [NSString stringWithFormat:@"%d", i], [NSString stringWithFormat:@"第%d", i]];
     }
     [db commit];

     //数据查询
     FMResultSet *cursor = [db executeQuery:@"select * from persons"];
     int nCols = cursor.columnCount;
     while ([cursor next]) {
         for (int i=; i<nCols; i++) {
             printf("%s ", [[cursor stringForColumnIndex:i] UTF8String]);
         }
         printf("\n");
     }
     cursor = nil;

     //关闭数据库
     [db close];

     //删除数据库测试文件
     [[NSFileManager defaultManager] removeItemAtPath:dbfile error:nil];

 }

 BOOL isfile(NSString *path)
 {
     NSFileManager *fileManager = [NSFileManager defaultManager];
     BOOL isdir = NO;
     if ([fileManager fileExistsAtPath:path isDirectory: &isdir]) {
         return isdir == NO;
     }
     return NO;
 }

 BOOL isdir(NSString *path)
 {
     NSFileManager *fileManager = [NSFileManager defaultManager];
     BOOL isdir = NO;
     if ([fileManager fileExistsAtPath:path isDirectory: &isdir]) {
         return isdir == YES;
     }
     return NO;
 }