为什么这段代码在另一个解决方案中不起作用？

Question

我当前的解决方案中有以下代码，它返回错误“值”无效”。下面的 sn-p 已被缩短，仅显示问题区域，而不是整个 ActionResult。

        Dim tComment As New hdComment

        tComment.Comment = collection("wmd-input")
        tComment.MadeOn = DateTime.Now
        tComment.UserID = Session("LoggedInUser")
        tComment.CallID = id

        If Not tComment.Comment.Trim().Length = 0 Then
            db.hdComments.InsertOnSubmit(tComment)
        End If

        db.SubmitChanges()

        Return Redirect("/Calls/Details/" & id)

但是，在之前的项目中，我使用了完全相同的代码，即使视图相同，但仍然返回上述错误。

一切正常。

唯一不同的是它是一个不同的项目。

我对这个有点不知所措。

有人有什么想法吗？

---

EDIT作为参考，这里是整个ActionResult。

'
' POST: /Calls/Details/5
<Authorize()> _
<AcceptVerbs(HttpVerbs.Post)> _
<ValidateInput(False)> _
Function Details(ByVal id As Integer, ByVal collection As FormCollection) As ActionResult

    Dim calls As hdCall = callRepository.GetCall(id)

    ViewData("MyCallID") = calls.CallID
    ViewData("UserThatLogged") = calls.UserID

    ViewData("TimeLogged") = calls.loggedOn.ToLongDateString & " " & calls.loggedOn.ToLongTimeString
    ViewData("Title") = calls.Title

    Dim dataContext As New CustomerServiceModelDataContext
    ViewData("Status") = New SelectList(dataContext.hdStatus, "StatusID", "Status", calls.StatusID)
    ViewData("Type") = New SelectList(dataContext.hdCategories, "CategoryID", "Title", calls.CategoryID)
    ViewData("Company") = calls.hdCompany.Company
    ViewData("Priority") = New SelectList(dataContext.hdPriorities, "PriorityID", "Priority", calls.PriorityID)
    ViewData("CallDetails") = calls.CallDetails
    ViewData("Customer") = calls.hdCustomer.CustomerName
    ViewData("CustomerID") = calls.hdCustomer.CustomerID
    ViewData("CustomerCallCount") = callRepository.CountCallsForThisCustomer(calls.hdCustomer.CustomerID).Count()
    ViewData("ContactNumber") = calls.hdCustomer.Telephone
    ViewData("AssignedTo") = New SelectList(dataContext.aspnet_Users, "UserName", "UserName", calls.AssignedTo)


    Dim callComments = callRepository.GetCallComments(id)
    Dim db As New CustomerServiceModelDataContext

    Try
        Dim tComment As New hdComment

        tComment.Comment = collection("wmd-input")
        tComment.MadeOn = DateTime.Now
        tComment.UserID = Session("LoggedInUser")
        tComment.CallID = id

        If Not tComment.Comment.Trim().Length = 0 Then
            db.hdComments.InsertOnSubmit(tComment)
        End If

        'Update any call changes
        Dim tCall = (From c In db.hdCalls _
                     Where c.CallID = id _
                     Select c).SingleOrDefault


        tCall.updatedOn = DateTime.Now
        tCall.UpdatedBy = Session("LoggedInUser")
        tCall.StatusID = collection("Status")
        tCall.AssignedTo = collection("AssignedTo")
        tCall.CategoryID = collection("Type")
        tCall.PriorityID = collection("Priority")

        db.SubmitChanges()

        Return Redirect("/Calls/Details/" & id)

    Catch ex As Exception
        ModelState.AddModelError("Error", ex)
        Return View(callComments)
    End Try

    Return View(callComments)
End Function

其余的代码可以正常工作，如果 wmd-input 字段在表单上留空，只有当其中有内容时才会抛出错误。

EDIT 对此行的一点更新：

If Not tComment.Comment.Trim().Length = 0 Then

现在读取

If (Not tComment.Comment.Trim().Length = 0) Then

如果 wmd 输入框中没有内容，则页面更新，但如果有，则返回 The value '' is invalid.

Answer 1

您可能缺少参考。或者框架版本不同。

也是同一台开发机，两个地方都安装了asp.net-mvc吗？

Answer 2

我设法解决了这个问题，问题实际上在于 hdCalls 和 hdComments 之间的外键约束。

我删除了约束并重新创建了它们，突然之间就很好了。