sqlite3增删查改应用
前端之家收集整理的这篇文章主要介绍了
sqlite3增删查改应用，
前端之家小编觉得挺不错的，现在分享给大家，也给大家做个参考。
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
3.创建viewController控制器，布局好界面
@H_
502_36@
ViewController.h:
@H_
502_36@
#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:
@H_
502_36@
#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,&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],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],errorMsg); } char * del = "delete from FIELDS where id = ?;"; sqlite3_stmt * stmt; if(sqlite3_prepare_v2(database,del,nil) == sqlITE_OK) { sqlite3_bind_int(stmt,[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],errorMsg); } char * update = "update FIELDS set id = ?,name = ? where id = ?"; sqlite3_stmt * stmt; if(sqlite3_prepare_v2(database,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,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],errorMsg); } NSString * query = @"select * from FIELDS where id = ?"; sqlite3_stmt * statement; if(sqlite3_prepare_v2(database,[query UTF8String],&statement,nil) == sqlITE_OK) { sqlite3_bind_int(statement,[self.txtSearchBar.text intValue]); //sqlite3_bind_text(statement,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
