如何将string []转换为字典 <int, string> 使用单独的int []作为键集？

Question

I know that Linq offers the ToDictionary(key, value) method, and I'm sure there's a way to be able to do what I'm trying to achieve but I can't quite figure it out.

I have two arrays, the first being conditionalIds , which is simply an int[] that stores a number of Ids, the second array is a string[] called conditionalAnswers . I essentially want to combine and map these two arrays so that each of the Ids stores in conditionalIds maps to the correct answer.

var conditionalIds = _currentRuleSet.MultiConditionalQuestionIds;
var conditionalAnswers = _currentRuleSet.MultiConditionalQuestionAnswers;
var map = conditionalAnswers.ToDictionary(conditionalIds, x => x[]);

However I'm not sure how to structure the Linq query to achieve this.

Answer 1

Assuming both lists have the same number of items and they are in the correct order, you want to use Linq Enumerable.Zip , for example this will give you an IEnumerable of an anonymous type:

var map = conditionalIds.Zip(
    conditionalAnswers, 
    (id, answer) => new { id, answer });

And if you really want a dictionary:

var dictionary = map.ToDictionary(x => x.id, x => x.answer);

Answer 2

Ans given by @SeM is correct, but one thing is that question id array should have unique values.

    int[] queId={6,4,9,2,10};
string[] answers ={"Ans1", "Ans3","Ans4","Ans16","Ans18"} ;
Dictionary<int, string> queAnsBank=answers.select((value,index)=>new{Key=queId[index],Value=value}).ToDictionary(i=>i.Key,i=>i.Value);

You can also achieve this by for loop.

Answer 3

It looks like target dictionary could be constructed as:

        Dictionary<int, string> map = conditionalIds.ToDictionary(
            keySelector: id => id,
            elementSelector: id => conditionalAnswers[id]);

Answer 4

If you are trying to map based on conditionalAnswers and conditionalIds indices, you can do something like this:

var map = conditionalAnswers
          .Select((s, i) => new { Key = conditionalIds[i], Value = s })
          .ToDictionary(d => d.Key, d => d.Value);

References: Enumerable.Select Method