bubdm / dynamicstruct Goto Github PK

This project contains two MS VS2010 Solutions: a simple class library that uses reflection to create a struct from an XML file, and a simple WinForms app that uses the library to create the struct in memory and tells you if it worked (or not). 

For example, you have a struct in which you won't know the field names or data types until runtime. But let's say that at runtime, you want a struct that look like this:

using System;
using System.Runtime.InteropServices;

namespace MyGreatProject
{
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Pack = 1)]
    struct MyCoolStruct
    {
        public System.Double Latitude;
        public System.Double Longitude;
        public System.Int32 Altitude;
    }
}

The code supplied will create that struct for you in memory, assuming it finds an XML file like this:

<?xml version="1.0" encoding="utf-8"?>
<StructFieldCollection xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <DataSet>
    <StructField>
      <Name>Latitude</Name>
      <DataType>System.Double</DataType>
    </StructField>
    <StructField>
      <Name>Longitude</Name>
      <DataType>System.Double</DataType>
    </StructField>
    <StructField>
      <Name>Altitude</Name>
      <DataType>System.Int32</DataType>
    </StructField>
  </DataSet>
</StructFieldCollection>

What could you use this for? Hmm... 

I use it for a vendor-specific API that requires a struct defining each of the (possibly hundreds) of variables you want to read to/write from their system. Keeping this straight and trying to quickly test the addition/removal of a field or two got unmanageable. 

But you could pass Windows messages (WM_COPYDATA / Marshal.PtrToStructure...) from one app to another without having to compile each app every time you changed the structure of the data in the message. (Of course you could do this also with UDP packets sent to/from localhost, or a message bus, or a shared database, or possibly even smoke signals. But that's for another project...)