Question

我正在尝试在Razor视图页面上以'foreach'语法显示分组列表。我该怎么办？

I made list like this. It works.
*before you read this: 'columnName1' is string, 'ColumnName2' is double.

//控制器---

var list = db.xxx.where(x => x.ID == 92).ToList();
return View(list);

//view---

<table class="">


@foreach (var controllerName in modle)
{
 <tr>
  <td>@controllerName.ColumnName1</td>
  <td>@controllerName.ColumnName2</td>
 </tr>
}

我尝试在下面进行分组和求和。 //控制器

var list = db.xxx.where(x => x.ID == 92).ToList();

var list1 = list
.GroupBy(y => y.columnName1)
            .Select(group => new
            {
            columnName1 = group.Key,
            columnName2 = group.Sum(x => x.columnName2)
            })
            .ToList();


            return View(list1);

我希望显示包含分组和求和的列表。

//表

columnName1  | columnName2(sum result)
USA          |  12
JAPAN        |  10

Answer 1

您需要为此创建一个视图模型类，因为现在您正在将一个匿名对象传递给您的视图，从技术上讲，可以使用dynamic来实现，但是我不鼓励这样做。如果您出错了，强类型视图总是会给您带来编译时错误：

public class CountryViewModel
{
    public string Name { get; set;}
    public double Result {get; set;}
}

然后更改您的操作方法以将该类返回视图：

var list1 = list.GroupBy(y => y.columnName1)
                .Select(group => new CountryViewModel
                {
                    Name = group.Key,
                    Result = group.Sum(x => x.columnName2)
                })
                .ToList();


 return View(list1);

在您的视图中，将模型定义更改为该视图模型类

@model Namespace.To.Your.CountryViewModel

最后，您可以在每个循环中再次使用智能感知和模型绑定：

@foreach (var item in Model)
{
   <tr>
      <td>@item.Name</td>
      <td>@item.Result</td>
   </tr>
}

Answer 2

    it is almost same with marco's answer. 

    --make a view model

    public class CountryViewModel
    {
        public string Name { get; set;}
        public double Result {get; set;}
    }
    --at the controller need put 'ViewModel Name'
    var list1 = list.GroupBy(y => y.columnName1)
                   .Select(group => new CountryViewModel
                    {
                        Name = group.Key,
                        Result = group.Sum(x => x.columnName2)
                    })
                    .ToList();


     return View(list1);

--foreach was same (i didn't need @model syntax on the top in this case.
@foreach (var item in Model)
{
   <tr>
      <td>@item.Name</td>
      <td>@item.Result</td>
   </tr>
}

如何在“剃刀视图”页面上显示分组列表？

2 个答案: