Visual C/C++ projects are XML files but they have a different file extension (*.vcproj).
Having to change an option to through tens of projects files each with more than one platform (Win32, Win64, Windows Mobile) and multiple configurations (Debug, Release) only by loading the projects in Visual Studio and clicking through the UI is not very appealing.
Since we already know that the project files are XML files one can write a program / script to change the desired option, in my case the change of the C runtime library - dynamic / static.
I have chosen WSH JScript, MSXML 3.0 and XPath to write a script to change Visual C/C++ projects. My decision was due two arguments: JScript is present on Windows XP, and the scripts can be debugged by Visual Studio 2005+ (//X command line parameter).
During the development I have stumbled on a XPath query problem, the function contains was not found in msxml3.dll. The problem was due to the fact that MSXML 3.0 was not instructed to use XPath as selection language (xmlDoc.setProperty("SelectionLanguage", "XPath");). Newer MSXML versions do not have this requirement though.
The message boxes displayed when issued from command line like change_runtime.js myproject.vcproj are due to the fact that JScript is not the default scripting language in WSH. One solution is to call the script like: cscript change_runtime.js myproject.vcproj, which requires some typing, the other solution is to change the default scripting language in WSH, which can be accomplished by running cscript //H:CScript.
The source code can be found here. Changing Visual C/C++ projects just become easier for me :-)