C#通过NameValueCollection迭代 [英] C# Iterate through NameValueCollection
问题描述
我有一个 NameValueCollection
,并希望遍历这些值。目前,我这样做,但似乎应该有一个更简洁的方法来做:
NameValueCollection nvc = new NameValueCollection();
nvc.Add(Test,Val1);
nvc.Add(Test2,Val1);
nvc.Add(Test2,Val1);
nvc.Add(Test2,Val2);
nvc.Add(Test3,Val1);
nvc.Add(Test4,Val4);
foreach(nvc中的字符串)
foreach(nvc.GetValues中的字符串v)
Console.WriteLine({0} {1},s, v)。
Console.ReadLine();
有吗?
您可以使用Linq整理集合,但它仍然是 foreach
循环,但现在更隐式。
var items = nvc.AllKeys.SelectMany(nvc.GetValues,(k,v)=> new {key = k,value = v});
foreach(项目中的var项)
Console.WriteLine({0} {1},item.key,item.value);
第一行将嵌套集合转换为匿名对象的(非嵌套)集合,属性键和值。
它现在是映射键 - >值而不是键 - >值集合 >。示例数据:
之前:
Test - > [Val]
Test2 - > [Val1,Val1,Val2],
Test3 - > [Val1] p>
Test4 - > [Val4]
$ b
测试 - > Val,
Test2 - > Val1,
Test2 - > Val1,
Test2 - > Val2,
Test3 - > Val1 ,
Test4 - > Val4
I have a NameValueCollection
, and want to iterate through the values. Currently, I’m doing this, but it seems like there should be a neater way to do it:
NameValueCollection nvc = new NameValueCollection();
nvc.Add("Test", "Val1");
nvc.Add("Test2", "Val1");
nvc.Add("Test2", "Val1");
nvc.Add("Test2", "Val2");
nvc.Add("Test3", "Val1");
nvc.Add("Test4", "Val4");
foreach (string s in nvc)
foreach (string v in nvc.GetValues(s))
Console.WriteLine("{0} {1}", s, v);
Console.ReadLine();
Is there?
You can flatten the collection with Linq, but it's still a foreach
loop but now more implicit.
var items = nvc.AllKeys.SelectMany(nvc.GetValues, (k, v) => new {key = k, value = v});
foreach (var item in items)
Console.WriteLine("{0} {1}", item.key, item.value);
The first line, converts the nested collection to a (non-nested) collection of anonymous objects with the properties key and value.
It's flatten in the way that it's now a mapping key -> value instead of key -> collection of values. The example data:
Before:
Test -> [Val],
Test2 -> [Val1, Val1, Val2],
Test3 -> [Val1],
Test4 -> [Val4]
After:
Test -> Val,
Test2 -> Val1,
Test2 -> Val1,
Test2 -> Val2,
Test3 -> Val1,
Test4 -> Val4
这篇关于C#通过NameValueCollection迭代的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!