使用xml linq创建元素：

Imports System.Xml
Imports System.Xml.Linq
Imports System.IO
Module Module1

    Sub Main()

        Dim xml As String =
            "<?xml version=""1.0"" encoding=""utf-8""?>" + _
            "<soap:Envelope xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xmlns:xsd=""http://www.w3.org/2001/XMLSchema"" xmlns:soap=""http://schemas.xmlsoap.org/soap/envelope/"">" + _
                "<soap:Body>" + _
                    "<GetAnOfficerRolesResponse xmlns=""http://tempuri.org/"">" + _
                        "<GetAnOfficerRoles>" + _
                        "</GetAnOfficerRoles>" + _
                    "</GetAnOfficerRolesResponse>" + _
                "</soap:Body>" + _
            "</soap:Envelope>"

        Dim Envelope As XDocument = XDocument.Parse(xml)

        Dim GetAnOfficerRoles As XElement = Envelope.Descendants().Where(Function(x) x.Name.LocalName = "GetAnOfficerRoles").FirstOrDefault()
        Dim ns As XNamespace = GetAnOfficerRoles.GetDefaultNamespace()

        While sqlreader2.Read()
            Dim officer As New XElement(ns + "Officer")
            GetAnOfficerRoles.Add(officer)

            officer.Add(New XElement(ns + "ID", sqlreader2("ID").ToString())
            officer.Add(New XElement(ns + "USERS", sqlreader2("USERS").ToString())
            officer.Add(New XElement(ns + "ROLES", sqlreader2("ROLES").ToString())
        End While

        Dim settings As New XmlWriterSettings
        settings.Indent = True
        Dim mStream As New MemoryStream()
        Dim writer As XmlWriter = XmlWriter.Create(mStream, settings)
        Envelope.WriteTo(writer)
        writer.Flush()
        mStream.Position = 0
        Dim sReader As New StreamReader(mStream)
        Dim response As String = sReader.ReadToEnd()
    End Sub
End Module

无需序列化类或多余代码，只需按如下方式更改getroles即可完成此操作：

<WebMethod()>
    Public Function GetRoles(ByVal ID As String, ByVal ROLE As String) As String
        Dim log As String = ""
        Dim sqlconn As New SqlConnection
        Dim sqlconn2 As New SqlConnection
        Dim sqlcmd As New SqlCommand
        'Dim listOfficerRoles As New List(Of String)()
        Dim sb As System.Text.StringBuilder = New System.Text.StringBuilder("")

        Try
            sqlconn2.ConnectionString = STR_CONFIG
            Dim sqlcmd2 = New SqlCommand
            sqlcmd2.Connection = sqlconn2
            sqlconn2.Open()
            Dim sqlquery2 = "select a.LOGIN,a.USER,
                                    STUFF((select ', ' + CAST(ROLE AS  VARCHAR(1000)) from STROLE b where 
                                    b.USER = a.USER
                                    FOR XML PATH('')),1,1,'') AS ROLES 
                                    from T_USER a where ID = @ID
                                    group by a.ID, a.LOGIN"
            With sqlcmd2
                .Connection = sqlconn2
                .CommandText = sqlquery2
                .CommandType = CommandType.Text
                .Parameters.AddWithValue("@ID", ID)
            End With
            sqlcmd2.CommandText = sqlquery2
            Dim ds = New DataSet()
            Dim sqlreader2 = sqlcmd2.ExecuteReader()
            If sqlreader2 IsNot Nothing And sqlreader2.HasRows Then
                While sqlreader2.Read()

                    'listOfficerRoles.Add(sqlreader2("LOGIN").ToString)
                    'listOfficerRoles.Add(sqlreader2("ID").ToString)
                    'listOfficerRoles.Add(sqlreader2("ROLES").ToString)
                    sb.AppendLine("<RECORDS>")
                    sb.AppendLine(String.Format("<LOGIN>{0}</LOGIN>", sqlreader2("LOGIN").ToString))
                    sb.AppendLine(String.Format("<ID>{0}</ID>", sqlreader2("ID").ToString))
                    sb.AppendLine(String.Format("<ROLES>{0}</ROLES>", sqlreader2("ROLES").ToString))
                    sb.AppendLine("</RECORDS>")
                End While
            End If

            'Return listOfficerRoles
            Return String.Format("<DOCUMENT>{0}</DOCUMENT>", sb.ToString)

    End Function

然后从客户端可以详细说明作为xml接收的字符串。