iOS 数据库的增删改查(OC版)

时间:2021-02-14 22:55:38

自己写了几个方法来实现数据的增删改查功能:

首先在TARGETS---》》Build phases里面添加数据库所关联的库文件libsqlite3.tbd

添加完以后,在控制器上添加

#import <sqlite3.h> 且增加属性

{

sqlite3 *db;

}

在.m文件中实现增删改查的方法即可

#import "ViewController.h"

#define DBNAME    @"personinfo.sqlite"

#define NAME      @"name"

#define AGE       @"age"

#define ADDRESS   @"address"

#define TABLENAME @"PERSONINFO"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {

[super viewDidLoad];

// Do any additional setup after loading the view, typically from a nib.

[self OpenDataBase];

[self createTable];

[self InsertData];

[self SelectData];

[self deleteData];

[self updateData];

}

#pragma mark-----------打开数据库

-(void)OpenDataBase

{

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *documents = [paths objectAtIndex:0];

NSString *database_path = [documents stringByAppendingPathComponent:DBNAME];

if (sqlite3_open([database_path UTF8String], &db) != SQLITE_OK) {

sqlite3_close(db);

NSLog(@"数据库打开失败");

}

}

#pragma mark----------创建数据表PERSONINFO的语句

-(void)createTable

{

NSString *sqlCreateTable = @"CREATE TABLE IF NOT EXISTS PERSONINFO (ID INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, age INTEGER, address TEXT)";

[self execSql:sqlCreateTable];

}

#pragma mark------------创建一个独立的执行sql语句的方法

-(void)execSql:(NSString *)sql

{

char *err;

if (sqlite3_exec(db, [sql UTF8String], NULL, NULL, &err) != SQLITE_OK) {

sqlite3_close(db);

NSLog(@"数据库操作数据失败!");

}

}

#pragma mark------------增加数据

-(void)InsertData

{

NSString *sql1 = [NSString stringWithFormat:

@"INSERT INTO '%@' ('%@', '%@', '%@') VALUES ('%@', '%@', '%@')",

TABLENAME, NAME, AGE, ADDRESS, @"张三", @"18",@"北京"];

NSString *sql2 = [NSString stringWithFormat:

@"INSERT INTO '%@' ('%@', '%@', '%@') VALUES ('%@', '%@', '%@')",

TABLENAME, NAME, AGE, ADDRESS, @"老四", @"19",@"深圳"];

[self execSql:sql1];

[self execSql:sql2];

}

#pragma mark----------------删除数据

-(void)deleteData

{

sqlite3_stmt *statement;

NSString *sqlStr = [NSString stringWithFormat:@"DELETE FROM PERSONINFO WHERE age = %d", 19];

//        NSString *sqlStr = [NSString stringWithFormat:@"DELETE FROM PERSONINFO"];

int result = sqlite3_prepare_v2(db, [sqlStr UTF8String], -1, &statement, NULL);

if (result == SQLITE_OK) {

if (sqlite3_step(statement) == SQLITE_ROW) {//觉的应加一个判断, 若有这一行则删除

if (sqlite3_step(statement) == SQLITE_DONE) {

sqlite3_finalize(statement);

sqlite3_close(db);

}

}

}

sqlite3_finalize(statement);

sqlite3_close(db);

NSLog(@"-------删除后---------");

[self SelectData];

}

#pragma mark----------修改数据

-(void)updateData

{

sqlite3_stmt *statement;

NSString *sqlStr = [NSString stringWithFormat:@"update PERSONINFO set name = '%@' where age = %d", @"王五", 18];

int result = sqlite3_prepare_v2(db, [sqlStr UTF8String], -1, &statement, NULL);

if (result == SQLITE_OK) {

if (sqlite3_step(statement) == SQLITE_ROW) {//觉的应加一个判断, 若有这一行则修改

if (sqlite3_step(statement) == SQLITE_DONE) {

sqlite3_finalize(statement);

sqlite3_close(db);

}

}

}

sqlite3_finalize(statement);

sqlite3_close(db);

NSLog(@"------修改后----------");

[self SelectData];

}

#pragma mark-----------------查询数据

-(void)SelectData

{

NSString *sqlQuery = @"SELECT * FROM PERSONINFO";

sqlite3_stmt * statement;

if (sqlite3_prepare_v2(db, [sqlQuery UTF8String], -1, &statement,nil) == SQLITE_OK) {

while (sqlite3_step(statement) == SQLITE_ROW) {

char *name = (char*)sqlite3_column_text(statement, 1);

NSString *nsNameStr = [[NSString alloc]initWithUTF8String:name];

int age = sqlite3_column_int(statement, 2);

char *address = (char*)sqlite3_column_text(statement, 3);

NSString *nsAddressStr = [[NSString alloc]initWithUTF8String:address];

NSLog(@"name:%@  age:%d  address:%@",nsNameStr,age, nsAddressStr);

}

}

sqlite3_close(db);

}

 
输出结果:

2016-12-10 08:55:54.130 SQLDemo[7313:144445] name:张三  age:18  address:北京

2016-12-10 08:55:54.130 SQLDemo[7313:144445] name:老四  age:19  address:深圳

2016-12-10 08:55:54.131 SQLDemo[7313:144445] -------删除后---------

2016-12-10 08:55:54.132 SQLDemo[7313:144445] name:张三  age:18  address:北京

2016-12-10 08:55:54.133 SQLDemo[7313:144445] ------修改后----------

2016-12-10 08:55:54.133 SQLDemo[7313:144445] name:王五  age:18  address:北京