c# - Linq 搜索不返回所有条目

Question

伙计们，我有两个问题...首先我有一个 linq 查询搜索，它查询姓名和姓氏并从数据库返回结果。例如，如果我搜索 John，它会返回完美的 John travolta(我的问题是)如果我搜索 john travolta 的名字和姓氏，它会找不到结果吗？...帮助。

问题二:再次搜索时如何清除搜索结果？因为当我第二次搜索时，上一次搜索的结果是

public class SearchResults
        {
            public string Name { get; set; }
            public string Surname { get; set; }

            public SearchResults(string name, string surname)
            {
                Name = name;
                Surname = surname;
            }



 protected void btnSearch_Click(object sender, EventArgs e)
        {
            string search = txtSearch.Text.ToLower().TrimEnd();
            lsSearchResults = null;
            lsSearchResults = new List<SearchResults>();
            Repeater1.DataSource = null;
            lsSearchResults.Clear();
            Repeater1.DataSource = "";
        }

        if (string.IsNullOrWhiteSpace(txtSearch.Text))
            {
              lblResults.Text = "Please enter a password & Em@ilAddress";

                lsSearchResults.Clear();

                return;
            }

        else
        {
            var found = (from User in myDB.Memberships
                         where User.Name.ToLower().Contains(txtSearch.Text.ToLower()) ||
                         User.Surname.ToLower().Contains(txtSearch.Text.ToLower())
                         select new { User.Name, User.Surname });

            // validates items in search query if Exist
            if (!ChillZARdev.App_Code.Utilities.IsEmpty(found))
            {
                foreach (var user in found)
                {
                    lsSearchResults.Add(new SearchResults(user.Name, user.Surname));
                    // ls.Add(user.Name + " " + user.Surname);

                    // Response.Write(user);
                }
                Repeater1.DataSource = lsSearchResults;

                Repeater1.DataBind();

             }
          }

Answer 1

简短的解决方案是在 where 子句中同时包含名字和姓氏:

var found = (from User in myDB.Memberships
             where User.Name.ToLower().Contains(txtSearch.Text.ToLower()) ||
             User.Surname.ToLower().Contains(txtSearch.Text.ToLower()) ||
             (User.Name + " " + User.Surname).ToLower().Contains(txtSearch.Text.ToLower())

但是，这意味着搜索“Travolta john”不会返回任何结果。

如果这很重要，您应该按空格拆分字符串，然后搜索每个单词。

List<string> searchSplit = txtSearch.Text.ToLower().Split(' ');

var found = (from User in myDB.Memberships
         where IsMatch(searchSplit, User)

private bool IsMatch(List<string> searchSplit, User User){
   return searchSplit.Count() ==
          searchSplit.Where(x => User.Name.ToLower().Contains(x) ||
                                 User.Surname.ToLower().Contains(x)).Count();
}

理想情况下，如 Steve B has commented , 最好实现一个预建的搜索引擎，它需要比简单的自定义搜索更多的搜索工具。但这取决于您的预算/要求。