Question

我想对SQL数据库中表的一列中的所有值求和并将其显示在页面加载本身上。我所做的是：

public ActionResult Sumthem() {
    string constr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
    SqlConnection con = new SqlConnection(constr);
    SqlCommand cmd = new SqlCommand("SELECT SUM (Final) FROM SomeTable", con);
    cmd.Connection.Open();    


    ViewBag.FinalSUM = cmd.ExecuteScalar().ToString();

    return View("Records");   
}

我要这样打印（在Records.cshtml视图中）：

@{var sum = ViewBag.FinalSUM;}
<h2>The Total is: @sum</h2>

我在哪里以及如何调用控制器方法？我在Razor中尝试过@Url.Action("Sumthem", "Records")，但未调用controller方法。页面加载后，如何返回和打印总和的值？

编辑：此后我尝试了此操作，但是出现了System.StackOverflow错误

@{Html.RenderAction("Sumthem", "Records");
var sum = ViewBag.FinalSUM;}
<h2>The Total is: @sum</h2>
//Returned PartialView instead of View from the Controller.

Answer 1

操作：

install.packages("captioner")
library(captioner)
table_nums <- captioner::captioner(prefix = "Table")
table_nums(name = "MyFirstTable", caption = "Caption")
table(c(1, 2, 3), c(1, 3, 3))

部分视图（Records.chstml）：

public ActionResult Sumthem() {
    string constr = System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        SqlCommand cmd = new SqlCommand("SELECT SUM (Final) FROM SomeTable", con);
        cmd.Connection.Open();

        ViewBag.FinalSUM = cmd.ExecuteScalar().ToString();

        return PartialView("Records", new YourModel())
    }   
}

用法（在实际上需要显示总值的任何视图中）：

@model YourModel
@*You can use data from your model as well*@
<h2>The Total is: @ViewBag.FinalSUM</h2>

ASP.NET MVC：如何在页面加载时打印从控制器返回到视图的变量？

1 个答案: