LINQ比较两个数组并返回不匹配的位置和值

Question

In grading student exams there are two arrays of characters which represent correct questions answers / student answers. The goal is grade and identify the missed questions and to display the question number and correct answer answer and student choice.

The code below loops through two arrays and identifies the missed questions. I would like to use LINQ to refactor the existing code. I have looked at the .except, .union and .intersect operators but don't feel they are the right fit for the task at hand. What standard query operators are reasonable to use to calculate the correct results and what would this code look like?

void Main()
{
    char[] correctAnswer ="ACBCDABCABDDCCBA".ToCharArray();
    char[] studentsChoice = "ABBCDDBCAADDACCA".ToCharArray();

    for( int x = 0; x<=correctAnswer.Count()-1;x++)
    {
        if( ! correctAnswer[x].Equals(studentsChoice[x]))
        {
            Console.WriteLine(String.Format("Question:{0} correctAnswer:{1}  StudentsChoice:{2}",x,  correctAnswer[x],studentsChoice[x]));
        }
}

Output

    Question:1 AnswerKey:C Correct:B
    Question:5 AnswerKey:A Correct:D
    Question:9 AnswerKey:B Correct:A
    Question:12 AnswerKey:C Correct:A
    Question:14 AnswerKey:B Correct:C

Answer 1

You can add indexing to your answer keys and then simply compare it

    string[] result = studentsChoice.Select((c,i)=> new { index = i, choice = c })
    .Where(c=> c.choice != correctAnswer[c.index])
    .Select(c => $"Question:{c.index+1} AnswerKey:{c.choice} Correct:{correctAnswer[c.index]}")
.ToArray();

String formatting with older C# versions:

    string[] result = studentsChoice.Select((c,i)=> new { index = i, choice = c })
    .Where(c=> c.choice != correctAnswer[c.index])
    .Select(c => string.Format("Question:{0} AnswerKey:{1} Correct:{2}",c.index+1,c.choice,correctAnswer[c.index]))
.ToArray(); 

please check the working DEMO