FMDB使用注意事项

1、数据格式必须是NSObject对象，即使在数据表中是整型（integer）、浮点型（float），如

    NSString * dishId = [_infoDictionary objectForKey:@"id"];
    NSString * dishName = [_infoDictionary objectForKey:@"name"];
    NSString * specialPrice = [NSString stringWithFormat:@"%@",[_infoDictionary objectForKey:@"favorablePrice"]];
    NSString * price = [NSString stringWithFormat:@"%@",[_infoDictionary objectForKey:@"price"]];
    NSString * countStr = @"1";
    BOOL insert = [database executeUpdate:@"insert into menu values (?,?,?,?,?)",dishId,dishName,specialPrice,price,countStr];

上面是正确的代码，如果使用如下格式插入数据，则会bad access..

    NSString * dishId = [_infoDictionary objectForKey:@"id"];
    NSString * dishName = [_infoDictionary objectForKey:@"name"];
    NSString * specialPrice = [_infoDictionary objectForKey:@"favorablePrice"];
    NSString * price = [_infoDictionary objectForKey:@"price"];
    NSString * countStr = @"1";
    BOOL insert = [database executeUpdate:@"insert into menu values (?,?,?,?,?)",dishId,dishName,specialPrice,price,countStr];

注意，

[_infoDictionary objectForKey:@"price"]与

[_infoDictionary objectForKey:@"favorablePrice"]
是浮点型字符串，如@"12.5"