sqlite3---代码操作

1.创建数据库

NSString * docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject];

NSLog(@"%@",docPath);

NSString * filePath = [docPath stringByAppendingPathComponent:@"stu.sql"];

if (sqlite3_open([filePath UTF8String], &_mySQL)!=SQLITE_OK) {

NSLog(@"open error");

return 0;

}

NSLog(@"open ok");

2.创建表

NSString *createTablesql = @"create TABLE IF NOT EXISTS Student (id integer primary key autoincrement,name varchar(20),address varchar(20),icon blob)";

char *error = nil;

if (sqlite3_exec(_mySQL, [createTablesql UTF8String], nil, nil, &error)!=SQLITE_OK) {

NSLog(@"creat table error");

return 0;

}

NSLog(@"creat table ok");

3.插入数据

NSString *insertSql =  @"insert into Student (name,address,icon) values (?,?,?)";

sqlite3_stmt *statement;

if (sqlite3_prepare_v2(mysql, [insertSql  UTF8String], -1, &statement, NULL) != SQLITE_OK) {

NSLog(@"insert prepare error");

return;

}else{

NSLog(@"insert prepare ok");

NSData * imageData = UIImagePNGRepresentation(self.iconImageView.image);

sqlite3_bind_text(statement, 1, [_nameTextField.text UTF8String], -1, NULL);

sqlite3_bind_text(statement, 2, [_addTextField.text UTF8String], -1, NULL);

sqlite3_bind_blob(statement, 3, [imageData bytes], (int)[imageData length], NULL);

if(sqlite3_step(statement)!=SQLITE_DONE){

NSLog(@"insert error");

}else{

NSLog(@"insert ok");

}

}

sqlite3_finalize(statement);

4.查询数据

NSString *selectSql = @"select * from Student";

sqlite3_stmt *statement;

if (sqlite3_prepare_v2(mysql, [selectSql UTF8String], -1, &statement, NULL) != SQLITE_OK) {

NSLog(@"read prepare error");

return;

}else{

NSLog(@"read prepare ok");

while (sqlite3_step(statement)==SQLITE_ROW) {

Student * stu = [[Student alloc]init];

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

char * address = (char *)sqlite3_column_text(statement, 2);

Byte * bytes = (Byte *)sqlite3_column_blob(statement, 3);

int length = sqlite3_column_bytes(statement, 3);

NSData * data = [NSData dataWithBytes:bytes length:length];

UIImage * image = [UIImage imageWithData:data];

stu.name = [NSString stringWithUTF8String:name];

stu.address = [NSString stringWithUTF8String:address];

stu.icon = image;

[_studentArray addObject:stu];

}

}