有没有一种方法可以通过字符串引用数组元素 [英] Is there a way to refer to an array element by string

问题描述

嘿，

有谁知道用字符串引用制作数组的方法(如PHP):

$data["shopping"]["item1"] = "item name";

在vb.net中，我喜欢这样做

Hey,

Does anybody know a way to make array (like in PHP) with a string reference:

$data["shopping"]["item1"] = "item name";

In vb.net I do it like

dim data(1,1) as string<br />
data(0,0)="item name"

但是读回代码更困难...

我知道您必须在vb中使用之前定义数组大小，
但是有没有办法通过字符串引用数组元素?

(data("shopping","item1")="item name")

but it''s more difficult to read back the code...

I Know you have to define the array size before using in vb,
but is there a way to refer to an array element by string?

( data("shopping","item1")="item name" )

Thanks!!

推荐答案

data ["shopping"] ["item1"] =商品名称";

在vb.net中，我喜欢这样做

data["shopping"]["item1"] = "item name";

In vb.net I do it like

dim data(1,1) as string<br />
data(0,0)="item name"

但是读回代码更困难...

我知道您必须在vb中使用之前定义数组大小，
但是有没有办法通过字符串引用数组元素?

(data("shopping","item1")="item name")

谢谢！！！

but it''s more difficult to read back the code...

I Know you have to define the array size before using in vb,
but is there a way to refer to an array element by string?

( data("shopping","item1")="item name" )

Thanks!!

您最好的选择可能是双 Dictionary:

Your best bet is probably a double Dictionary:

Dim data As New Dictionary(Of String, Dictionary(Of String, String))

data("shopping") = New Dictionary(Of String, String)
data("shopping")("item1") = "item name"

我认为这是不可能的.但是，您可能要使用列表(T) [ ^ ]或
编辑，我知道我的答案没有得到充分解释:
如果您使用具有唯一ID的类，则可能只需要一个List(Of T)，然后可以通过LINQ查询通过其ID进行引用.

I do not think that is possible. However, you might want to use a List(Of T)[^] or Dictionary(Of T)[^]. They are a bit more ''.NETty'' and easier to use. There is a small difference between Arrays and Lists(Of T), but when used correctly I don''t think Arrays can do anything that Lists(Of T) can''t. Of course some Array/List(Of T) pro will now prove me wrong... ;p

Edit, I understood my answer was not sufficiently explained:
If you use a Class with a unique ID you would probably only need a List(Of T) which you can then reference by its ID through, perhaps a LINQ query.

Dim shoppingList As New List(Of ShoppingItem)
Dim item = (From i In shoppingList.Items Where i.ID = "item1").FirstOrDefault 'From the top of my head.

当确实需要Dictionary(Of T)时，可以将其Key用作字符串，在OP的情况下为"ItemName"，并使用一个表示Item的Class.我怀疑这只是一个字符串.在大多数现实世界中的应用中，您都会拥有一个班级.

When you do need a Dictionary(Of T) you could use its Key as a string, in OP''s case "ItemName" and a Class that represents Item. I doubt it is only a String. In most real world apps you''d have a Class.

Dim shoppingDict As New Dictionary(Of String, ShoppingItem)
Dim item = shoppingDict.Item("ItemName") ' This returns the ShoppingItem Class with that item name.

如果您只需要一个包含字符串的项目，则应该看到cPallini的答案.

If you would need an item which only has a string you should see cPallini''s answer.

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