通过键&获取哈希表obj改变其公共财产 [英] Get hashtable obj by key & change its public properties

问题描述

首先，我声明一个哈希表及其值.哈希表条目的键是GUID，值是带有几个字符串值的对象.

First of all I declare a hashtable and its values. The key of a hashtable entry is a GUID and the value is an object with a few string values.

    Guid g = Guid.NewGuid();
    Hashtable hash = new Hashtable();
    InstallationFiles instFiles = new InstallationFiles(string1, string2, string3);
    hash.Add(g, instFiles);
    //...add many other values with different GUIDs...

我的目标是使用户可以编辑字符串1，字符串2，字符串3.简而言之，我处于可以编辑该条目的"GUID g"的位置:

My goal is to give a user a possibility to EDIT string 1, string2, string3. To cut a long story short, I am in a position where I can get the "GUID g" of the entry which needs to be edited:

   public void edit() 
   {
         //here I retrieve the GUID g of the item which has to be edited:
         object objectHash = item.Tag;
         //here i loop through all hash entries to find the editable one:
         foreach(DictionaryEntry de in hash)
         {
            if(de.Key.ToString() == objectHash) 
            {
            //here I would like to access the selected entry and change string1 - 
           //the line below is not working.

            hash[de.Key].string1 = "my new value"; 
            }
         }

   }

我如何使这条线正常工作?

How do I make this line work?

    hash[de.Key].string1 = "my new value"; 

推荐答案

使用 Dictionary< Guid，InstallationFiles> 代替 HashTable

upd.您可以使用它.

upd. You can use this.

 (hash[de.Key] as InstallationFiles).string1 = "asdasd" 

好，解释:

因为哈希表不是通用类型，所以它包含对键和值的引用作为对象.

Because Hashtable is not generic type, it contains references on keys and values as Objects.

这就是为什么当您访问值 hashtable [mykey] 时，您引用了 Object .要使其成为对您的类型( InstallationFiles )的引用，您必须从对 Object 的引用"获得对 InstallationFiles 的引用".在我的示例中，我使用" as "运算符执行此操作.

Thats why, when you access to your value hashtable[mykey], you got reference to Object. To make it as reference to your type (InstallationFiles), you have to from "reference to Object" get "reference to InstallationFiles". Im my sample I use "as" operator to do this.

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