How to pass multiple values to web service in VB.net

Question

I have created a form in VB.net, where on-click of a button multiple variables are passed to a web service. My code is as below :

Imports MySql.Data.MySqlClient
Imports OutlookAddIn2.mantistest
Dim QService As New MantisConnectPortTypeClient

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim value1 As String
Dim value2 As String
Dim value3 As String
Dim value4 As String
Dim viewstate As String


value1 = Project_Name.SelectedItem.ToString()
value2 = ComboBox2.SelectedItem.ToString()
value3 = ComboBox3.SelectedItem.ToString()
value4 = TextBox4.Text
Dim s As String = String.Format("Value 1: {0} value2 : {1} value3: {2} value4: {3}", value1, value2, value3, value4)
Windows.Forms.MessageBox.Show(s)

TextBox1.Text = QService.mc_issue_add(username:="**", password:="**", issue:="view_state:{0} project{1}")

End Sub

 

The input parameters of my web service are :

1. Project
2. Category
3. Priority
4. Status

When I try to put them in following ways I get the following errors :

1. Code : 

   issue:=("Category:{0} project{1}",value1, value2)

• Error : value1 saying that a named argument is expected.
2. Code : 

   TextBox1.Text = QService.mc_issue_add(username:="**", password:="**", view_state:=value1, Project:=value2)

• Error : Argument not specified for parameter issue of public function QService.mc_issue_add(Username as String, Password as String, issue as mantistest.Issuedata)As string

This is the function for that particular module in the webservice

Function mc_issue_add(ByVal username As String, ByVal password As String, ByVal issue As mantistest.IssueData) As <System.ServiceModel.MessageParameterAttribute(Name:="return"), System.Xml.Serialization.SoapElementAttribute(DataType:="integer")> String

 

Where have I gone wrong? I have tried using other arguments with single input values and it works fine. Appreciate any assistance.