Public Class Sample

    Public Sub CodeSample_gettasks()
        Dim strXML As String = String.Empty

        Dim dsOutput As DataSet = Nothing
        Dim guid As String = String.Empty
        Dim sb As New System.Text.StringBuilder
        Try
            sb = New System.Text.StringBuilder
            'Building API QueryString
            sb.Append("fct=gettasks")
            sb.Append(String.Format("&guid={0}", "d7894cc8-6499-4a29-8274-a625f14c530a"))
            sb.Append(String.Format("&projectid={0}", "NULL"))
            sb.Append(String.Format("&portfolioid={0}", "NULL"))
            sb.Append(String.Format("&taskid={0}", "NULL"))
            sb.Append(String.Format("&assignedprojectsonly={0}", False))
            sb.Append(String.Format("&includeinactivetemplates={0}", True))
            sb.Append(String.Format("&projectstatictemplate={0}", "NULL"))
            sb.Append(String.Format("&filtertaskgroupid={0}", "NULL"))
            sb.Append(String.Format("&filtertaskstatusid={0}", "NULL"))
            sb.Append(String.Format("&isgroupingtaskstatus={0}", "NULL"))
            sb.Append(String.Format("&filterhasdocuments={0}", "NULL"))
            sb.Append(String.Format("&filtertaskcompleted={0}", "NULL"))
            sb.Append(String.Format("&filtertasktypeid={0}", "NULL"))
            sb.Append(String.Format("&filtertaskpriorityid={0}", "NULL"))
            sb.Append(String.Format("&filtercreatoruserid={0}", "NULL"))
            sb.Append(String.Format("&filterassigneduserid={0}", "NULL"))
            sb.Append(String.Format("&filterassignedusergroupid={0}", "NULL"))
            sb.Append(String.Format("&filterrevieweruserid={0}", "NULL"))
            sb.Append(String.Format("&filteronuseridmustmeetall={0}", True))
            sb.Append(String.Format("&filterprojecttypeid={0}", "NULL"))
            sb.Append(String.Format("&filterclientid={0}", "NULL"))
            sb.Append(String.Format("&filterfirstdate={0}", "NULL"))
            sb.Append(String.Format("&filterfirstdateoperator={0}", "NULL"))
            sb.Append(String.Format("&filterfirstdatevalue={0}", "NULL"))
            sb.Append(String.Format("&filterseconddate={0}", "NULL"))
            sb.Append(String.Format("&filterseconddateoperator={0}", "NULL"))
            sb.Append(String.Format("&filterseconddatevalue={0}", "NULL"))
            sb.Append(String.Format("&filtertaskassigned={0}", "NULL"))
            sb.Append(String.Format("&filtertaskreviewers={0}", "NULL"))
            sb.Append(String.Format("&filtermarkedonly={0}", "False"))
            sb.Append(String.Format("&filtersoontodoonly={0}", "False"))
            sb.Append(String.Format("&filtersoondueonly={0}", "False"))
            sb.Append(String.Format("&filteroverdueonly={0}", "False"))
            sb.Append(String.Format("&filteroverduerecent={0}", "False"))
            sb.Append(String.Format("&filterrecurrencynumber={0}", "NULL"))
            sb.Append(String.Format("&filtertasksreadytostartonly={0}", False))
            sb.Append(String.Format("&filtertaskswithoutdates={0}", False))
            sb.Append(String.Format("&texttosearch={0}", "NULL"))
            sb.Append(String.Format("&getplaintextvalues={0}", False))
            sb.Append(String.Format("&sortorder={0}", "NULL"))
            sb.Append(String.Format("&useshowhide={0}", False))
            sb.Append(String.Format("&forcombo={0}", False))
            sb.Append(String.Format("&pagenumber={0}", "NULL"))
            sb.Append(String.Format("&rowsperpage={0}", "NULL"))
            sb.Append(String.Format("&asynccall={0}", False))
            sb.Append(String.Format("&asynccallid={0}", "NULL"))
            sb.Append(String.Format("&exportdomainevaleur={0}", "NULL"))
            sb.Append(String.Format("&exporttype={0}", "NULL"))
            sb.Append(String.Format("&exportdelimiter={0}", "NULL"))
            sb.Append(String.Format("&exportdecimalsymbol={0}", "NULL"))
            sb.Append(String.Format("&exportlcid={0}", 0))
            sb.Append(String.Format("&exportonscreencolumnsonly={0}", True))
            sb.Append(String.Format("&exportview={0}", 0))
            sb.Append(String.Format("&exportviewother={0}", "NULL"))
            sb.Append(String.Format("&exportfieldstodisplay={0}", "NULL"))
            sb.Append(String.Format("&exportremovehtmlonly={0}", True))
            sb.Append(String.Format("&exportenablefilterxls={0}", False))
            sb.Append(String.Format("&format={0}", "DS"))

            'Calling API
            strXML = CallHttp("https://api.aceproject.com/", sb.ToString)
            'Retreive Output structure generate by API
            dsOutput = Deserialize(Of DataSet)(strXML)
            If dsOutput IsNot Nothing AndAlso dsOutput.Tables.Count > 0 Then
                If dsOutput.Tables.Contains("dtAPIErrors") Then
                    Throw New Exception(String.Format("{0}: {1}", _
                                                      dsOutput.Tables(0).Rows(0).Item("ErrorNumber").ToString, _
                                                      dsOutput.Tables(0).Rows(0).Item("ErrorDescription").ToString))
                End If
            End If
        Catch ex As Exception
            Throw
        Finally
            If sb IsNot Nothing Then sb = Nothing
            If dsOutput IsNot Nothing Then
                dsOutput.Dispose()
                dsOutput = Nothing
            End If
        End Try
    End Sub

    Private Shared Function CallHttp( ByVal url As String, _ 
                                      ByVal params As String) As String
        Dim loHttp As System.Net.HttpWebRequest
        loHttp = CType(System.Net.WebRequest.Create(url), System.Net.HttpWebRequest)
        loHttp.Method = "POST"
        Dim requestWriter As System.IO.StreamWriter = New System.IO.StreamWriter(loHttp.GetRequestStream())

        If Not String.IsNullOrEmpty(params) Then
            requestWriter.Write(params)
        End If
        requestWriter.Close()
        loHttp.ContentType = "application/x-www-form-urlencoded"
        loHttp.Headers.Set("Pragma", "no-cache")
        loHttp.AllowAutoRedirect = True
        loHttp.KeepAlive = True
        loHttp.Timeout = 30 * 1000

        Dim loWebResponse As System.Net.HttpWebResponse = CType(loHttp.GetResponse(), System.Net.HttpWebResponse)
        Dim enc As Encoding = System.Text.Encoding.UTF8
        Dim loResponseStream As System.IO.StreamReader = New System.IO.StreamReader(loWebResponse.GetResponseStream(), enc)
        Dim lcHtml As String = loResponseStream.ReadToEnd()

        loWebResponse.Close()
        loResponseStream.Close()

        Return lcHtml
    End Function


    Private Shared Function Deserialize(Of T)( ByVal strXML As String) As T
        Dim objet As T = Nothing
        Dim objType As Type = GetType(T)
        Try
            If Not String.IsNullOrEmpty(strXML) Then
                Dim objSerializer As New System.Xml.Serialization.XmlSerializer(objType)
                Dim objText As New System.Text.StringBuilder()
                Dim objXmlReader As New System.IO.StringReader(strXML)
                objet = DirectCast(objSerializer.Deserialize(objXmlReader), T)
                objXmlReader.Close()
            End If
            Return objet
        Catch ex As Exception
            Throw
        Finally
            If objet IsNot Nothing Then objet = Nothing
        End Try
    End Function

End Class