scala 从集合中获取元素
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/24571444/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Get element from Set
提问by blue-sky
How can I get element at position in Set ?
如何在 Set 中的位置获取元素？
For a List can do :
对于列表可以做：
val s : Set[(String, String)] = Set( ("a","b") )
val l1 = l(0)
But for Set :
但是对于 Set ：
val s : Set[(String, String)] = Set( ("a","b") )
val t1 = s(1)
I get compile time error :
我得到编译时错误：
Multiple markers at this line - type mismatch; found : Int(1) required: (String, String) - type mismatch; found :
Int(1) required: (String, String)
Update :
更新 ：
converting to List is an option but I though should be able to access a element at position in Set
转换为 List 是一个选项，但我虽然应该能够访问 Set 中某个位置的元素
回答by senia
Setis not an ordered collection - you can't get element by index.
Set不是有序集合 - 您无法按索引获取元素。
You could use headmethod to get single element from Set(it's not the first element, just some element).
您可以使用head方法从中获取单个元素Set（它不是第一个元素，只是某个元素）。
You could also process all elements using foreachmethod:
您还可以使用foreach方法处理所有元素：
for (s <- Set("a", "b")) println(s)
If you want to get all elements in some order you should convert Setto Sequsing toSeqmethod like this:
如果你想以某种顺序获取所有元素，你应该转换Set为Seq使用这样的toSeq方法：
val mySeq = mySet.toSeq
