IOS NSData/NSArray数组存储为SQLite blob

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为了避免各种类型的反复解析，可以将很多图像、数组、Byte 等转换为NSDate 再保存到blob 类型。

例1： NSData 、Byte 数组（指针）用FMDB 保存到SQLite 的blob

1、数据源

...................

Byte *msgbyte =malloc(sizeof(Byte*)*(48)) ;

//Byte[64].....

NSData *btData = [[NSDataalloc]initWithBytes:msgbytelength:length];

2、表

CREATE TABLE maininfo (
...
message_ blob
);

3. Model

@interface ParameterSet : NSObject

@property (nonatomic,copy)NSData* message;

4. DAO保存

+ (void)insertPS: (ParameterSet *) ps{

if ([shareDataBaseopen]) {

[shareDataBaseexecuteUpdate:

@"INSERT INTO maininfo (time_stamp,message_) VALUES(?,?)",ps.time_stamp,ps.message];

5. DAO 查询

ParameterSet *ps = [[ParameterSetalloc]init];

if ([shareDataBaseopen]) {

FMResultSet *s = [shareDataBaseexecuteQuery:[NSStringstringWithFormat:@"SELECT * FROM maininfo WHERE sys_no = '%@' and id_ = '%ld'",sysNo,(long)psId]];

if ([snext]) {

ps.ID = [s intForColumn:@"id_"];

ps.message = [s dataForColumn:@"message_"];

例2：NSArray用FMDB 保存到SQLite 的blob

1. NSArray 转为 NSData

NSData *data = [NSKeyedArchiver archivedDataWithRootObject:NSarray];

2. 保存NSData到SQLite blob

[database executeQuery:@"insert into save_article values (?,?)", model.Id, data

3.NSData转为NSArray

NSArray *array = [NSKeyedUnarchiver unarchiveObjectWithData:[database dataForColumn:@"yourcololumname"]];

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