c# 根据日期获取星期方法

protected void Page_Load(object sender, EventArgs e)
    {
        int m = System.DateTime.Today.Month;
        int y = System.DateTime.Today.Year;
        int d = System.DateTime.Today.Day;
        int weeks = getWeekDay(y, m, d);
        switch (weeks)
        {
            case 1:
                this.TextBox1.Text = "星期一";
                break;
            case 2:
                this.TextBox1.Text = "星期二";
                break;
            case 3:
                this.TextBox1.Text = "星期三";
                break;
            case 4:
                this.TextBox1.Text = "星期四";
                break;
            case 5:
                this.TextBox1.Text = "星期五";
                break;
            case 6:
                this.TextBox1.Text = "星期六";
                break;
            case 7:
                this.TextBox1.Text = "星期日";
                break;
        }
       
       
    }

 

    /// <summary>根据日期，获得星期几</summary>
    /// <param name="y">年</param>
    /// <param name="m">月</param>
    /// <param name="d">日</param>
    /// <returns>星期几，1代表星期一；7代表星期日</returns>
    public static int getWeekDay(int y, int m, int d)
    {
        if (m == 1) m = 13;
        if (m == 2) m = 14;
        int week = (d + 2 * m + 3 * (m + 1) / 5 + y + y / 4 - y / 100 + y / 400) % 7 + 1;
        return week;
    }