Question

我在C＃中为SharePoint webpart做一些自定义代码。具体来说，我正在进行测验，我的主要观点是解决问题清单，答案选择和正确答案。

在测验的最后阶段，我需要检查用户根据列表中的正确答案选择的答案。目前，我正在做以下检查是否每个都是正确的，我假设它不是很有效，因为它遍历每个问题。是否有一种方法，特别是对于SPList foreach循环，哪种方法更有效？

                // 1. Store questions and answers in class
                    List<submittedAnswers> answeredQuestions = new List<submittedAnswers>();

                // 2. From POST pull answered question IDs and answer IDs (which correspond to the question primary key and answer choice number both stored in the list)
                    // INSERT BEAUTFIUL AND EFFICIENT WHILE LOOP HERE

                // 3. Loop through each question is list, if question was given, test if correct/incorrect
                using (SPWeb myWeb = mySite.OpenWeb())
                {
                    SPList answerList = myWeb.Lists[questionList];
                    foreach (SPListItem quizEntry in answerList.Items)
                    {
                        int pullAnswerId = int.Parse(quizEntry["Answer"].ToString()); // Pull answer number from list
                        int pullQuestionId = int.Parse(quizEntry["ID"].ToString()); // Pull primary key of question

                        submittedAnswers result = answeredQuestions.Find(delegate(submittedAnswers e) { return e.questionId == int.Parse(quizEntry["ID"].ToString()); });
                        if (result != null)
                        {
                            if (result.responseId != pullAnswerId) // If the response was different from the answer
                                incorrectAnswers++;
                            else
                                correctAnswers++;
                        }
                    }
                }
                // C# quiz grading magic here....

Answer 1

如果您需要访问列表中的每个项目，那么使用foreach就完全可以了：

SPList answerList = myWeb.Lists[questionList];
foreach (SPListItem quizEntry in answerList.Items)
{
    // todo...
}

通常，大多数人需要使用列表中的一部分项目。在这种情况下，您很可能希望从列表中检索项目的子集，然后进行处理。例如，通过使用SPQuery和SPList.GetItems（code from the full example here）：

// Build a query.
SPQuery query = new SPQuery();
query.Query = string.Concat(
                    "<Where><Eq>",
                        "<FieldRef Name='Status'/>",
                        "<Value Type='CHOICE'>Not Started</Value>",
                    "</Eq></Where>",
                    "<OrderBy>",
                        "<FieldRef Name='DueDate' Ascending='TRUE' />",
                        "<FieldRef Name=’Priority’ Ascending='TRUE' />", 
                    "</OrderBy>");                    

query.ViewFields = string.Concat(
                          "<FieldRef Name='AssignedTo' />",
                          "<FieldRef Name='LinkTitle' />",
                          "<FieldRef Name='DueDate' />",
                          "<FieldRef Name='Priority' />");

query.ViewFieldsOnly = true; // Fetch only the data that we need.

// Get data from a list.
string listUrl = web.ServerRelativeUrl + "/lists/tasks";
SPList list = web.GetList(listUrl);
SPListItemCollection items = list.GetItems(query);

仅供参考......以下是其他一些选项的良好链接：https://www.nothingbutsharepoint.com/sites/devwiki/SP2007Dev/Pages/Accessing%20list%20items%20using%20the%20object%20model.aspx

SharePoint有很多工具。始终值得确定哪种工具适合手头的工作。：）

Answer 2

这可能看起来很愚蠢，但不是使用类来存储变量，为什么不使用简单的数组呢？或者更简单的方法是编写一个sql查询来将答案数组与存储在数据库中的答案进行比较。你的解决方案似乎是很多OO魔法，但也许只是我。

另请查看答案Performance of Arrays vs. Lists

看起来使用for循环比使用foreach循环迭代列表会更快。

Answer 3

我认为使用带有正确格式查询的SpList.GetItems会给出正确答案的数量。

U2U CAML Query Builder工具可用于获取正确的查询。

Answer 4

为什么不在Sharepoint中使用LINQ？它非常简单，无需循环

即

SPLinqDataContext dc = new SPLinqDataContext(SPContext.Current.Web.Url);

EntityList<QuizItem> Answers = dc.GetList<QuizItem>("Quiz");
EntityList<QuestionsItem> Questions = dc.GetList<QuestionsItem>("Questions");

int iCorrectAnswers = (from q in Questions
            from a in Answers
            where (q.Question == a.Question) && (q.CorrectAnswer == a.Answer)
            select a).Count();

int iWrongAnswers = (from q in Questions
                        from a in Answers
                        where (q.Question == a.Question) && (q.CorrectAnswer != a.Answer)
                        select a).Count();

这是使用LINQ in Sharepoint

的指南

最有效的C＃SharePoint List迭代

4 个答案: