iOS中自动实现对象序列化的方法详解

2020-01-20 12:39:34王振洲

其次进行解档, 原理和归档差不多, 直接上代码


- (instancetype)initWithCoder:(NSCoder *)aDecoder
{
 self = [self init];
 if (self) {

  unsigned int count;
  Ivar *varArray = class_copyIvarList([self class], &count);

  for (int i = 0; i < count; i++) {
   Ivar var = varArray[i];
   const char *cName = ivar_getName(var); // 属性名c字符串
   NSString *proName = [[NSString stringWithUTF8String:cName] substringFromIndex:1]; //OC字符串,并且去掉下划线 _
   const char *cType = ivar_getTypeEncoding(var); // 获取变量类型,c字符串
   NSString *proType = [NSString stringWithUTF8String:cType]; // oc 字符串

   if ([proType containsString:@"NSString"]) {
    proType = stringType;
   }
   if ([proType containsString:@"NSNumber"]) {
    proType = numberType;
   }
   if ([proType containsString:@"NSArray"]) {
    proType = arrayType;
   }
   if ([proType containsString:@"UIImage"]) {
    proType = imageType;
   }

   if ([proType isEqualToString:intType] || [proType isEqualToString:boolType] || [proType isEqualToString:BoolType]) {
    int32_t number = [aDecoder decodeInt32ForKey:proName];
    [self setValue:@(number) forKey:proName];
   }
   else if ([proType isEqualToString:longTpye]) {
    int64_t number = [aDecoder decodeInt64ForKey:proName];
    [self setValue:@(number) forKey:proName];
   }
   else if ([proType isEqualToString:floatType]) {
    float number = [aDecoder decodeFloatForKey:proName];
    [self setValue:@(number) forKey:proName];
   }
   else if ([proType isEqualToString:longlongType] || [proType isEqualToString:doubleType]) {
    double number = [aDecoder decodeFloatForKey:proName];
    [self setValue:@(number) forKey:proName];
   }
   else if ([proType isEqualToString:stringType]) { // string 类型
    NSString *string = [aDecoder decodeObjectForKey:proName];
    [self setValue:string forKey:proName];
   }
   else if ([proType isEqualToString:numberType]) {
    NSString *number = [aDecoder decodeObjectForKey:proName];
    [self setValue:number forKey:proName];
   }
   else if ([proType isEqualToString:arrayType]) {
    NSArray *array = [aDecoder decodeObjectForKey:proName];
    [self setValue:array forKey:proName];
   }
   else if ([proType isEqualToString:imageType]) { // image 类型
    UIImage *image = [UIImage imageWithData:[aDecoder decodeDataObject]];
    [self setValue:image forKey:proName];
   }
  }
 }
 return self;
}

最后也就是 存储方法 、 清除存储的本地缓存 和 获取本地存储数据的方法


//存储路径
- (NSString *)filePathWithUniqueFlagString:(NSString *)uniqueFlag
{
 NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
 NSString *detailPath = [NSString stringWithFormat:@"%@_%@",uniqueFlag,[NSString stringWithUTF8String:object_getClassName(self)]];
 NSString *path = [docPath stringByAppendingPathComponent:detailPath];
 return path;
}


//保存对象数据到本地
- (void)saveDataToLocalWithUniqueFlagKey:(NSString *)uniqueFlagKey
{
 [NSKeyedArchiver archiveRootObject:self toFile:[self filePathWithUniqueFlagString:uniqueFlagKey]];
}


//清空本地存储的对象数据
- (id)getDataFromLocalWithUniqueFlagKey:(NSString *)uniqueFlagKey
{
 return [NSKeyedUnarchiver unarchiveObjectWithFile:[self filePathWithUniqueFlagString:uniqueFlagKey]];
}


//从本地获取对象数据
- (BOOL)removeDataFromLocalWithUniqueFlagKey:(NSString *)uniqueFlagKey
{
 NSError *error = nil;
 [[NSFileManager defaultManager] removeItemAtPath:[self filePathWithUniqueFlagString:uniqueFlagKey] error:&error];
 if (!error) {
  return YES;
 }
 else {
  return NO;
 }
}