Question

I am getting this error message when I try to ‘Add Web Reference’ to my ASMX proxy project:

**'To be XML serializable, types which inherit from ICollection must have an    implementation of Add(System.String) at all levels of their inheritance hierarchy. System.Collections.Specialized.NameValueCollection does not implement Add(System.String)'** 

I need to pass name-value pairs to my web service and here is what I came up with:

public class FileService : System.Web.Services.WebService {      [WebMethod]     public string UploadFile(byte[] incomingArray         , string FileName         , long FileLengthInBytes         , NameValueCollection nvcMetaData) 

I now realize I need help changing this (I am new to C# and this part of the .Net framework). If I can get this working, my web service will need to be invoked by ColdFusion (right now I am using an .aspx page for calling the web service). So whatever means I come up with for passing a variable number of NAME-VALUE pairs I need it callable by CF. Thanks in advance.

Answer 1

As an alternative, you can just define a simple NameValue class and receive an array.

public class NameValue {    public string Name{get;set;}    public string Value{get;set;} }  [WebMethod] public string UploadFile(byte[] incomingArray     , string FileName     , long FileLengthInBytes     , NameValue[] nvcMetaData) 

If on the client side you have a NameValueCollection you can easily map to your type. Check the sample I posted in this question