在投递到其他Actionmethod时错误调用actionmethod

Question

我从下面的Ajax调用actionmethod UpdateDiscount：

function updateDiscount(e) {
        e.preventDefault();        
        var supplierOrderId = $("#supplier-order-id").val();
        var discount = $("#discount-input").val();
        console.log("supplierOrderId: " + supplierOrderId);
        console.log("discount: " + discount);
        $.ajax({
            url: '/supplierorder/updatediscount',
            type: "POST",
            data: { supplierOrderId: supplierOrderId, discount: discount },
            success: function (response) {
                alert("success");
                $("#supplier-order-table-container").html(response);
            },
            error: function (xhr, textStatus, errorThrown) {
                console.log(xhr);
                console.log(textStatus);
                console.log(errorThrown);
            }
        });
    }

UpdateDiscount的签名如下所示：

<HttpPost()>
Public Function UpdateDiscount(supplierOrderId As Integer, discount As Decimal) As ActionResult

但是，我得到了一个500个内部错误：

The parameters dictionary contains a null entry for parameter 'id' of non-nullable type 
'System.Int32' for method 'System.Web.Mvc.ActionResult 
Details(Int32, System.Web.Mvc.FormCollection)' in 'xxx.yyy.SupplierOrderController'.

由于某种原因，调用了Details操作方法。值得一提的是，我在该方法中放置的断点没有被击中。UpdateDiscount的断点也没有被击中。我真的不明白这里有什么问题。我像这样使用Ajax来调用项目中其他地方的操作方法。

编辑. route.config (对不起VB :P)：

routes.MapRoute("SupplierOrderDetails", "supplierorder/{id}", New With {.controller = "SupplierOrder", .action = "Details"})
...
routes.MapRoute( _
            "Default", _
            "{controller}/{action}/{id}", _
            New With {.controller = "Home", .action = "Index", .id = UrlParameter.Optional} _
        )

有什么想法吗？

Answer 1

尝试添加带有约束的路由，并检查它在本例中是否适合您。

要么尝试添加HTTP谓词路由约束。

我不能百分之百肯定我的VB.net技能，但我希望你知道怎么做

routes.MapRoute("SupplierOrderDetails", "supplierorder/{id}", New With {.controller = "SupplierOrder", 
 action = "Details"},
 New With { httpMethod = new HttpMethodConstraint("GET") 
)

或者添加Regex约束，如下所示

routes.MapRoute("SupplierOrderDetails", "supplierorder/{id}", New With {.controller = "SupplierOrder", 
 action = "Details"},
 New With {.Id= "\d+"}
)

在这些违禁品的帮助下，它不会将url路由到详细操作并跳过它。

如果您不想走这条路，并且希望避免写约束。您应该更改您的url模式，并使用路由更改您指定此url的所有位置。

routes.MapRoute("SupplierOrderDetails", "supplierorderdetails/{id}", New With {.controller = "SupplierOrder", 
 action = "Details"}
)