In the past, the team I belong to has made vailable "super samples" which provide a broad range of coverage-by-example around specific messaging APIs - these are often referred to as API Explorers. Two examples of these are MFCMAPI (for Extended MAPI) and EWSEditor (Exchange Web Services). There is a third one which has been used internally for many years, however has not been made public until now - WebStoreExplore, which covers most supported WebDAV operations. If your doing WebDAV development against Exchange, troubleshooting or learning how to use it, then this should be a valuble sample/tool to have.
WebStoreExplore (WSE) provides the ability to navigate mailboxes and public folders, view and modify content, read/write/parse/validate mime, convert strings, isssue WebDAV commands and OWA commands (such as used for getting Free/Busy information), use authenticaiton such as FBA/BasicAuth/NTLM. One of the helpful features is WebDavCommand, which allows for quick testing of WebDAV calls and provides samples another is the abiltiy to compare properties of two items by URL.
WSE was built upon code written to troubleshot Microsoft customer issues across many years. It should be a valuable resource to see how EWS calls can be done. WSE is considered a sample and as such you will assume ownership and responsibility for what the code does. I chose VB.NET for this application since it was the easiest language to port code to and from C# and VB6; much of the code was written with this in mind. You will find a bit of the code being a bit verbose in some areas - however this was done in order to aid in order to aid in debugging specific WebDAV issues.