function switchMenu(tarLyr,w){
	//NNの場合
	if (document.layers) {
		tarLyrObj = document.layers[tarLyr];
	}
	//IE・NN6の場合
	if (document.getElementById) {
		tarLyrObj = document.getElementById(tarLyr).style;
	}
	if (w=='hide') {
		tarLyrObj.visibility = 'hidden';
	} else if (w=='show') {
		tarLyrObj.visibility = 'visible';
	} else if (tarLyrObj.visibility=='visible'||tarLyrObj.visibility=='show'){
		tarLyrObj.visibility = 'hidden';
	} else {
		tarLyrObj.visibility = 'visible';
	}
}