创建一个数据库(包括int 类型的id,string 类型的name),并对其进行增删改查
实现步骤:
1.创建一个SingleViewApplication应用。
sqlite3数据库可以采用MesaSQLite可视化工具
2.添加sqlite3支持的库文件,libsqlite3.dylib
3.创建viewController控制器,布局好界面
ViewController.h:
#import <UIKit/UIKit.h> @interface ViewController : UIViewController - (IBAction)addClick:(id)sender; - (IBAction)deleteClick:(id)sender; - (IBAction)updateClick:(id)sender; - (IBAction)selectClick:(id)sender; @property (retain, nonatomic) IBOutlet UITextField *idText; @property (retain, nonatomic) IBOutlet UITextField *nameText; - (IBAction)viewClick:(id)sender; @property (retain, nonatomic) IBOutlet UISearchBar *txtSearchBar; @end
ViewController.m:
#import "ViewController.h" #import <sqlite3.h> #define kFilename @"Homeworkdb.rdb" @interface ViewController () @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; } - (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning]; // Dispose of any resources that can be recreated. } -(NSString *)dataFilePath { NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString * document = [path objectAtIndex:0]; return [document stringByAppendingPathComponent:kFilename]; } //增加 - (IBAction)addClick:(id)sender { //创建 sqlite3 * database; if(sqlite3_open([[self dataFilePath] UTF8String], &database)!=SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Failed to open database"); } NSString * creataSQL = @"CREATE TABLE IF NOT EXISTS FIELDS" "(id INTEGER PRIMARY KEY,name TEXT);"; char * errorMsg; if(sqlite3_exec(database, [creataSQL UTF8String], NULL, NULL, &errorMsg)!=SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Error creating table:%s",errorMsg); } char * update = "insert or replace into FIELDS (id, name)" "values (?,?);"; sqlite3_stmt * stmt; if(sqlite3_prepare_v2(database, update, -1, &stmt, nil) == SQLITE_OK) { sqlite3_bind_int(stmt, 1, [self.idText.text intValue]); //1表示第一个问号 sqlite3_bind_text(stmt, 2, [self.nameText.text UTF8String], -1, NULL);//2表示第二个问号 } if(sqlite3_step(stmt)!=SQLITE_DONE) { NSAssert(0, @"Error updating table:%s",errorMsg); } sqlite3_finalize(stmt); //这句话不能漏 sqlite3_close(database); //关闭数据库 UIAlertView *a = [[UIAlertView alloc] initWithTitle:@"友情提示" message:@"添加成功" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil]; [a show]; } //删除 - (IBAction)deleteClick:(id)sender { sqlite3 * database; if(sqlite3_open([[self dataFilePath] UTF8String], &database)!=SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Failed to open database"); } NSString * creataSQL = @"CREATE TABLE IF NOT EXISTS FIELDS" "(id INTEGER PRIMARY KEY,name TEXT);"; char * errorMsg; if(sqlite3_exec(database, [creataSQL UTF8String], NULL, NULL, &errorMsg)!=SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Error creating table:%s",errorMsg); } char * del = "delete from FIELDS where id = ?;"; sqlite3_stmt * stmt; if(sqlite3_prepare_v2(database, del, -1, &stmt, nil) == SQLITE_OK) { sqlite3_bind_int(stmt, 1, [self.idText.text intValue]); //1表示第一个问号 } if(sqlite3_step(stmt)!=SQLITE_DONE) { NSAssert(0, @"Error delete table:%s",errorMsg); } sqlite3_finalize(stmt); sqlite3_close(database); UIAlertView *a = [[UIAlertView alloc] initWithTitle:@"友情提示" message:@"删除成功" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil]; [a show]; } //修改 - (IBAction)updateClick:(id)sender { sqlite3 * database; if(sqlite3_open([[self dataFilePath] UTF8String], &database)!=SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Failed to open database"); } NSString * creataSQL = @"CREATE TABLE IF NOT EXISTS FIELDS" "(id INTEGER PRIMARY KEY,name TEXT);"; char * errorMsg; if(sqlite3_exec(database, [creataSQL UTF8String], NULL, NULL, &errorMsg)!=SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Error creating table:%s",errorMsg); } char * update = "update FIELDS set id = ?,name = ? where id = ?"; sqlite3_stmt * stmt; if(sqlite3_prepare_v2(database, update, -1, &stmt, nil) == SQLITE_OK) { sqlite3_bind_int(stmt, 1, [self.idText.text intValue]); //1表示第一个问号 sqlite3_bind_text(stmt, 2, [self.nameText.text UTF8String], -1, NULL);//2表示第二个问号 sqlite3_bind_int(stmt, 3, [self.idText.text intValue]); } if(sqlite3_step(stmt)!=SQLITE_DONE) { NSAssert(0, @"Error updating table:%s",errorMsg); } sqlite3_finalize(stmt); //这句话不能漏 sqlite3_close(database); //关闭数据库 UIAlertView *a = [[UIAlertView alloc] initWithTitle:@"友情提示" message:@"修改成功" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil]; [a show]; } //查询 - (IBAction)selectClick:(id)sender { //创建数据库 sqlite3 * database; if(sqlite3_open([[self dataFilePath] UTF8String], &database)!=SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Failed to open database"); } NSString * creataSQL = @"CREATE TABLE IF NOT EXISTS FIELDS" "(id INTEGER PRIMARY KEY,name TEXT);"; char * errorMsg; if(sqlite3_exec(database, [creataSQL UTF8String], NULL, NULL, &errorMsg)!=SQLITE_OK) { sqlite3_close(database); NSAssert(0, @"Error creating table:%s",errorMsg); } NSString * query = @"select * from FIELDS where id = ?"; sqlite3_stmt * statement; if(sqlite3_prepare_v2(database, [query UTF8String], -1, &statement, nil) == SQLITE_OK) { sqlite3_bind_int(statement, 1, [self.txtSearchBar.text intValue]); //sqlite3_bind_text(statement, 2, [self.nameText.text UTF8String], -1, NULL); while(sqlite3_step(statement) == SQLITE_ROW) { int id = sqlite3_column_int(statement, 0); //0表示第1列 char * name = (char *)sqlite3_column_text(statement, 1); //1表示第2列 NSString * sid = [[NSString alloc] initWithFormat:@"%d",id]; NSString * sname = [[NSString alloc] initWithUTF8String:name]; self.nameText.text = sname; self.idText.text = sid; UIAlertView *a = [[UIAlertView alloc] initWithTitle:@"友情提示" message:@"查询成功" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil]; [a show]; } sqlite3_finalize(statement); } else { NSLog(@"error"); } sqlite3_close(database); } - (void)dealloc { [_idText release]; [_nameText release]; [_txtSearchBar release]; [super dealloc]; } - (IBAction)viewClick:(id)sender { [self.idText resignFirstResponder]; [self.nameText resignFirstResponder]; } @end
本文转蓬莱仙羽51CTO博客,原文链接:http://blog.51cto.com/dingxiaowei/1366418
,如需转载请自行联系原作者