// フォントサイズ変更Javascript

function WriteCookie(key, value, days) {  
	var str = key + "=" + escape(value) + ";";  
	if (days != 0) {  
		var dt = new Date();  
		dt.setDate(dt.getDate() + days);  
		str += "expires=" + dt.toGMTString() + ";";  
	}  
	document.cookie = str;  
}  
function ReadCookie(key) {  
	var sCookie = document.cookie;  
	var aData = sCookie.split(";");  
	var oExp = new RegExp(" ", "g");  
	key = key.replace(oExp, "");  

	var i = 0;  
	while (aData[i]) {  
		var aWord = aData[i].split("=");  
		aWord[0] = aWord[0].replace(oExp, "");  
		if (key == aWord[0]) return unescape(aWord[1]);  
		if (++i >= aData.length) break;  
	}  
	return "";  
}  
function DeleteCookie(key)   
{  
	var dt = new Date();  
	var str = key + "=;expires=" + dt.toGMTString();  
	document.cookie = str;  
}  

//ユーザー設定項目  
var defSize = 82; //規定サイズ  
var Unit = '%'       //単位  
var chWidth = 5;  //増減幅  
var days = 30;     //クッキー保存日数  
//設定項目終わり  

var x = defSize;  
function SetFontSize(v)  {  
	if (v > 10 && v < 300) {   
		document.body.style.fontSize = v + Unit;  
		if (defSize == v)  
			DeleteCookie('FontSize');  
		else  
		WriteCookie('FontSize', v, days);  
		x = v;  
	}  
}  
function FontSizeChange(cv) {  
	if (cv == 0)  
	SetFontSize(defSize);  
	else  
	SetFontSize(x + cv);  
}  
function ReadFontSize() {  
	fs = ReadCookie('FontSize')  
	if (fs != '') SetFontSize(fs);  
}