undefined.js

<?xml version="1.0" encoding="UTF-8" ?>
<package>
	<job>
		<script language = "JavaScript" src = "lib/underscore.js"></script>
		<script language = "JavaScript" src = "lib/json2.js"></script>
		<script language = "JavaScript">
		var Setting = function() {
			this.basePath = "C:\\app"
			// json files
			this.jsonFiles = [
					"setting\\one.json",
					"setting\\two.json"
					 ];
		}

		Setting.prototype.parseFiles = function(jsonFiles) {
			_.each(jsonFiles, function(file) {
				    var propName = file.match(/^.*\\(.*)\.json$/); // ex: one
				    this[propName[1]] = JSON.parse(includeFile(this.basePath + "\\" + file)); // setting.oneのようにしたいがthisがundefined
			});
		}

		var setting = new Setting();
		setting.parseFiles(setting.jsonFiles);
		WScript.Echo(setting.one.hoge); //one.jsonの値出力

		function includeFile(file) {
			var fso = new ActiveXObject("Scripting.FileSystemObject"),
			    fileStream = fso.openTextFile(file),
			    fileData = fileStream.readAll();

			fileStream.Close();

			return fileData;
		}
		</script>
	</job>
</package>