怎样用js根据当前星期几获取日期的

怎样用js根据当前星期几获取日期的。就是你随便输入1-7（分别代表一周），然后根据第一个输入的星期，返回对应的日期。

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todayDate = new Date();
date = todayDate.getDate();
month= todayDate.getMonth() +1;
year= todayDate.getYear();
document.write("今天是")
document.write("<br>")
if(navigator.appName == "Netscape")
{
document.write(1900+year);
document.write("年");
document.write(month);
document.write("月"顷州仿);
document.write(date);
document.write("日");
document.write("<br>")
}
if(navigator.appVersion.indexOf("MSIE") != -1)
{
document.write(year);
document.write("年");
document.write(month);
document.write("月");
document.write(date);
document.write("日"迹携);
}
if (todayDate.getDay() == 5) document.write("星期五")
if (todayDate.getDay() == 6) document.write("星期六")
if (todayDate.getDay() == 0) document.write("星期雀纤日")
if (todayDate.getDay() == 1) document.write("星期一")
if (todayDate.getDay() == 2) document.write("星期二")
if (todayDate.getDay() == 3) document.write("星期三")
if (todayDate.getDay() == 4) document.write("星期四")

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