Question

I wish to access many classes and variables, I would like to do this by dynamically setting the class name and variable name. Currently I am using

MyClass["myVariable1"]

to dynamically access the variable name

MyClass.myVariable1

I want to also dynanmically acces the class name, something like

["MyClass"]["myVariable1"]

But this does not work.

The purpose is that I have shared object with many user settings, I want to iterate through the shared object and set all the user settings across all the classes. I think if I cant dynamically access the class I must have a statement for each and every class name/variable.

Answer 1

我建议反对这种做法。虽然技术上可行，但就像欢迎应用程序架构中的灾难一样：

你依赖于你无法控制的东西：在Flash命名类的路上。
您将使用标识符重命名模糊处理来保护您的代码，因为它会使您的代码无效。
编译时错误检查优于运行时，您将把它留给运行时。如果在非调试环境中发生故障，您将永远不会知道。
下一个使用您的代码的开发人员（可能是您在几年内）将很难找到初始数据的来源。

所以，有了上述所有内容，我建议您切换到另一个模型：

options(stringsAsFactors = FALSE)
library(plyr)
library(dplyr)
library(xml2)

uuu_df <- data.frame(x = c('http://www.magicbricks.com/property-for-sale/residential-real-estate?bedroom=1&proptype=Multistorey-Apartment,Builder-Floor-Apartment,Penthouse,Studio-Apartment&cityName=Thane&BudgetMin=5-Lacs&BudgetMax=5-Lacs',
                           'http://www.magicbricks.com/property-for-sale/residential-real-estate?bedroom=2&proptype=Multistorey-Apartment,Builder-Floor-Apartment,Penthouse,Studio-Apartment&cityName=Thane&BudgetMin=5-Lacs&BudgetMax=5-Lacs',
                           'http://www.magicbricks.com/property-for-sale/residential-real-estate?bedroom=3&proptype=Multistorey-Apartment,Builder-Floor-Apartment,Penthouse,Studio-Apartment&cityName=Thane&BudgetMin=5-Lacs&BudgetMax=90-Lacs'))

urlList <- llply(uuu_df[,1], function(url){     

  this_pg <- read_html(url)

  results_count <- this_pg %>% 
    xml_find_first(".//span[@id='resultCount']") %>% 
    xml_text() %>%
    as.integer()

  if(results_count > 0){

    cards <- this_pg %>% 
      xml_find_all('//div[@class="SRCard"]')

    df <- ldply(cards, .fun=function(x){
      y <- data.frame(wine = x %>% xml_find_first('.//span[@class="agentNameh"]') %>% xml_text(),
                      excerpt = x %>% xml_find_first('.//div[@class="postedOn"]') %>% xml_text(),
                      locality = x %>% xml_find_first('.//span[@class="localityFirst"]') %>% xml_text(),
                      society = x %>% xml_find_first('.//div[@class="labValu"]') %>% xml_text() %>% gsub('\\n', '', .))
      return(y)
    })

  } else {
    df <- NULL
  }

  return(df)   
}, .progress = 'text')
names(urlList) <- uuu_df[,1]

bind_rows(urlList)

在主要课程中你打电话

package
{
    import flash.net.SharedObject;

    public class SharedData
    {
        static private var SO:SharedObject;

        static public function init():void
        {
            SO = SharedObject.getLocal("my_precious_shared_data", "/");
        }

        static public function read(key:String):*
        {
            // if (!SO) init();
            return SO.data[key];
        }

        static public function write(key:String, value:*):void
        {
            // if (!SO) init();
            SO.data[key] = value;
            SO.flush();
        }

        // Returns stored data if any, or default value otherwise.
        // A good practice of default application values that might
        // change upon user activity, e.g. sound volume or level progress.
        static public function readSafe(key:String, defaultValue:*):*
        {
            // if (!SO) init();
            return SO.data.hasOwnProperty(key)? read(key): defaultValue;
        }
    }
}

然后，每个以这些数据为基础的类都应该有一个初始化块：

SharedData.init();
// So now your shared data are available.
// If you are not sure you can call it before other classes will read
// the shared data, just uncomment // if (!SO) init(); lines in SharedData methods.

好吧，再说一次。上面的代码：

不使用奇怪的做法且易于理解
在每个班级中，任何人都可以清楚地看到数据来自哪里
将在编译时检查错误
可以进行模糊处理和保护

Answer 2

您可以尝试将该类放入变量并从那里开始：

var myClass:Class = getDefinitionByName("MyClass") as Class;
myClass["myVariable1"] = x;

Actionscript, can a class be accessed using a variable name?

2 个答案: