C# 如何在repeater中绑定前拆分字符串

我有这样一个Linq查询：

var result = from c in db.Class
                 join s in db.Students on c.Cls_Id equals s.Cls_Id
                 select new
                 {
                     s.Stud_Id,
                     s.FirstName,
                     c.Cls_Id,
                     c.Room,
                     c.Notification
                 };
repeater.DataSource = result.ToList();
repeater.DataBind();

但在通知字段中有这样的内容：C编程类/NTFF的这个房间。如果在标签

Text=''

中绑定，它将显示：这个C编程类房间/NTFF

我想将此字符串拆分为两个字符串，如下所示：

var result = from c in db.Class
                 join s in db.Students on c.Cls_Id equals s.Cls_Id
                 select new
                 {
                     s.Stud_Id,
                     s.FirstName,
                     c.Cls_Id,
                     c.Room,
                     c.Notification
                 };
repeater.DataSource = result.ToList();
repeater.DataBind();

str1=C编程类的这个房间

str2=NTFF

在将str1绑定到标签1和str2绑定到标签2之前。我怎样才能做到这一点？

您可以使用函数来获取str1，如下所示：-

 var result = from c in db.Class
                 join s in db.Students on c.Cls_Id equals s.Cls_Id
                 select new
                 {
                     s.Stud_Id,
                     s.FirstName,
                     c.Cls_Id,
                     c.Room,
                     str1 = c.Notification.Split('/').FirstOrDefault()
                 };

<asp:Lable Text='<%#DataBinder.Eval(Container.DataItem, "str1")%>'><asp:Label/>

public class Students
{
   public int Stud_Id { get; set; }
   public string FirstName{ get; set; }
   public int Cls_Id{ get; set; }
   public string Room{ get; set; }
   public string Notification{ get; set; }
   public string str1{ get; set; }
   public string str2{ get; set; }
}

List<Students> students = (from c in db.Class
                 join s in db.Students on c.Cls_Id equals s.Cls_Id
                 select new Students
                 {
                     Stud_Id = s.Stud_Id,
                     FirstName = s.FirstName,
                     Cls_Id = c.Cls_Id,
                     Room = c.Room,
                     Notification= c.Notification
                 }).ToList();

foreach (Student student in students)
{
    string[] Notifications = student.Notification.Split('/');
    student.str1 = Notifications.FirstOrDefault();
    student.str2 = Notifications.ElementAtOrDefault(1);
 }

然后，您可以将其绑定到标签，如下所示：-

 var result = from c in db.Class
                 join s in db.Students on c.Cls_Id equals s.Cls_Id
                 select new
                 {
                     s.Stud_Id,
                     s.FirstName,
                     c.Cls_Id,
                     c.Room,
                     str1 = c.Notification.Split('/').FirstOrDefault()
                 };

<asp:Lable Text='<%#DataBinder.Eval(Container.DataItem, "str1")%>'><asp:Label/>

public class Students
{
   public int Stud_Id { get; set; }
   public string FirstName{ get; set; }
   public int Cls_Id{ get; set; }
   public string Room{ get; set; }
   public string Notification{ get; set; }
   public string str1{ get; set; }
   public string str2{ get; set; }
}

List<Students> students = (from c in db.Class
                 join s in db.Students on c.Cls_Id equals s.Cls_Id
                 select new Students
                 {
                     Stud_Id = s.Stud_Id,
                     FirstName = s.FirstName,
                     Cls_Id = c.Cls_Id,
                     Room = c.Room,
                     Notification= c.Notification
                 }).ToList();

foreach (Student student in students)
{
    string[] Notifications = student.Notification.Split('/');
    student.str1 = Notifications.FirstOrDefault();
    student.str2 = Notifications.ElementAtOrDefault(1);
 }

然后，首先用如下查询填充自定义类：-

 var result = from c in db.Class
                 join s in db.Students on c.Cls_Id equals s.Cls_Id
                 select new
                 {
                     s.Stud_Id,
                     s.FirstName,
                     c.Cls_Id,
                     c.Room,
                     str1 = c.Notification.Split('/').FirstOrDefault()
                 };

<asp:Lable Text='<%#DataBinder.Eval(Container.DataItem, "str1")%>'><asp:Label/>

public class Students
{
   public int Stud_Id { get; set; }
   public string FirstName{ get; set; }
   public int Cls_Id{ get; set; }
   public string Room{ get; set; }
   public string Notification{ get; set; }
   public string str1{ get; set; }
   public string str2{ get; set; }
}

List<Students> students = (from c in db.Class
                 join s in db.Students on c.Cls_Id equals s.Cls_Id
                 select new Students
                 {
                     Stud_Id = s.Stud_Id,
                     FirstName = s.FirstName,
                     Cls_Id = c.Cls_Id,
                     Room = c.Room,
                     Notification= c.Notification
                 }).ToList();

foreach (Student student in students)
{
    string[] Notifications = student.Notification.Split('/');
    student.str1 = Notifications.FirstOrDefault();
    student.str2 = Notifications.ElementAtOrDefault(1);
 }

在此之后，只需使用参数

str1

和

str2

绑定标签即可使用

string.Replace（）

，如下所示：

<%# ((string)DataBinder.Eval(Container.DataItem, "Notification")).Replace("/NTFF", string.Empty) %>

然后在前端使用

FirstNotification

和

SecondNotification

属性。

---

注意：当没有“/”字符时，上面的代码将抛出索引越界异常。

您可以这样使用：首先创建一个DTO来存储结果实体，其中包含所有字段和一个额外字段来存储通知列表

public class Result
{
    public int Stud_Id { get; set; }
    ...
    ...
    public string Notification { get; set; }
    public string[] Notifications { get; set; }
}

List<Result> result = from c in db.Class
    join s in db.Students on c.Cls_Id equals s.Cls_Id
    select new Result
    {
        Stud_Id = s.Stud_Id,
        ...
        ...
        Notification = c.Notification
    }).ToList();

result.ForEach(r =>
    {
        r.Notifications = r.Notification.Split('/');
    });

---

现在，您可以使用要在标签中绑定的任何方法。

但它会显示如下错误消息：LINQ to Entities无法识别“System.String[]Split（Char[]）方法，并且该方法无法转换为存储表达式。@DucThoPham-Ohh您没有提到它正在使用实体框架。在这种情况下，您可以创建一个自定义类，并在收到查询中的数据后填充该类，并确保to必须调用

.ToList（）

，才能在内存中显示结果。您能帮我演示一下吗？@DucThoPham-如果这对您有帮助，您可以接受它作为答案：）抱歉，但我想将其插入2个字符串。如何获取所有2个字符串查看我的更新答案，并让我知道它是否适用于您。对不起，如何使用语法绑定？始终尝试自己做一些事情。检查Text=''是否可以完成您的任务。@DucThoPham-如果此解决方案解决了您的查询，请标记为“答案”，以便其他人可以从中受益。