值不能爲空，參數名稱：dataTable

我正在使用SQL數據庫，並從VB.Net調用存儲過程，但是當我嘗試並將我的數據表時，我收到錯誤，根據標題。值不能爲空，參數名稱：dataTable

我的代碼是：

Dim dt As DataTable 
Using sqlConn As New SqlConnection(_connstr) 
    Dim sqlcmd As New SqlCommand() 
    Dim dateParam = sqlcmd.Parameters.Add("@reportDate", SqlDbType.Date) 
    Dim dateParam2 = sqlcmd.Parameters.Add("@reportDateEndRange", SqlDbType.Date) 
    'Dim reportType = sqlcmd.Parameters.Add("@reportType", SqlDbType.VarChar) 
    Dim companyId = sqlcmd.Parameters.Add("@companyID", SqlDbType.Int) 
    dateParam.Value = DateTime.Now.AddDays(-1) 
    dateParam2.Value = DateTime.Today 
    'reportType.Value = "'IRF', 'TRF'" 
    companyId.Value = 1 

    sqlcmd.Connection = sqlConn 
    sqlcmd.CommandType = CommandType.StoredProcedure 
    sqlcmd.CommandText = "dbo.uspSearchRequest" 

    Using sqlda As New SqlDataAdapter(sqlcmd) 
     sqlda.Fill(dt) 
    End Using 
End Using

但是，當我站上罰球線sqlda.Fill(dt)我得到的錯誤爲每瓦。

我已經在存儲過程中測試了這些參數，並且我得到了結果。

有關如何阻止此問題的任何想法？

===========================編輯1

ALTER procedure [dbo].[uspSearchRequest] 
@reportDate date, 
@reportDateEndRange date, 
@companyID int 

as 
begin 

select 
null as [Report Manager], 
null as [Report Detail], 
null as [Form], 
null as [Attachment], 
req.OverallStatus as [Result], 
req.ReportNumber as [Report Number], 
req.ReportDate as [Report Date], 
req.FormNumber as [Form Number], 
req.SubmittedTimestamp as [Submit Date], 
req.ApplicantContactPerson as [Applicant] , 
req.Brand as [Brand], 
req.Department as [Department] 
from ias.dbo.request req 
where req.ReportDate between @reportDate and @reportDateEndRange 
and req.RequestCompanyID = @companyID 
end 
go

來源

2015-09-11 Code Warrior

大概推測'dt'爲null（Nothing）。我們不知道你在哪裏創建數據表... –

我的猜測是存儲過程需要其他一些你沒有指定的值，那麼默認情況下數據庫不允許爲null？你能否展示sproc的簽名？ –

在sqlda.Fill（dt）中放置一個斷點並檢查dt是否Nothing – Tuco