FMDB使用

下载fmdb,导入头文件FMDB.h

FMDatabase  * db;//一般定义属性在Appdelegate里面

获得document路径

NSString * documentPath=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, 1, YES)[0];

在document下拼接一个路径(一会生成的文件会直接在document文件夹下)

NSString * dbPath=[documentPath stringByAppendingString:@"/数据库.sqlite"];

初始化(或生成数据库文件)

db=[FMDatabase databaseWithPath:dbPath];

[db open];//如果不用这个方法则不会生成文件

创建表

if ([db open]) {

NSString * createTable=[NSString stringWithFormat:@"CREATE TABLE IF NOT EXISTS USERTABLE (id integer PRIMARY KEY AUTOINCREMENT, name text NOT NULL, age integer NOT NULL);"];

}

插入数据

NSString * insert=[NSString stringWithFormat:@"insert into USERTABLE(name,age) values('%@','%@')",name,age];

if ([db executeUpdate:insert]) {

NSLog(@"插入%@成功",name);

}

删除数据

NSString * delete=[NSString stringWithFormat:@"delete from USERTABLE where name='%@'",name];

if ([db executeUpdate:delete]) {

NSLog(@"删除%@成功",name);

}

修改数据(根据名字修改年龄)

NSString * change=[NSString stringWithFormat:@"UPDATE USERTABLE SET age='%@' where name='%@'",newAge,name];

if ([db executeUpdate:change]) {

NSLog(@"修改 %@ 成功",name);

}

查询数据(根据名字查询年龄)

NSString * select=[NSString stringWithFormat:@"select * from USERTABLE where name='%@'",name];

FMResultSet * set=[db executeQuery:select];

while ([set next]) {

NSString * age=[set stringForColumn:@"age"];

NSLog(@"%@年龄是%@",name,age);

}

遍历数据库

FMResultSet * resultSet=[db executeQuery:@"select * from USERTABLE"];

while ([resultSet next]) {

NSString * name=[resultSet stringForColumn:@"name"];

NSString * age=[resultSet stringForColumn:@"age"];

NSLog(@"%@ 今年 %@岁",name,age);

}