Eric的日期选择下拉列表小控件 dodo

利用JS实现日期选择功能,包括润年2月的日数变更, 简单实用!

主要属性: Date

设计时图示:  

源代码:

using System;
using System.ComponentModel;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

[assembly: TagPrefix("EFPlatform.WebControls", "efp")]
namespace EFPlatform.WebControls
{
    [DefaultProperty("Date")]
    [ToolboxData("<{0}:DateDropDownList runat=server></{0}:DateDropDownList>")]
    public class DateDropDownList : WebControl, INamingContainer
    {
        #region Properties

        #region Data(数据)
        #region Date
        [Bindable(true)]
        [Category("Data")]
        [DefaultValue("1900-1-1")]
        public DateTime Date
        {
            get
            {
                this.GetDate();
                return (ViewState["Date"] == null) ? (new DateTime(1900, 1, 1)) : (DateTime)ViewState["Date"];
            }

            set
            {
                ViewState["Date"] = value;
            }
        }
        #endregion

        #region FirstYear
        [Category("Data")]
        [DefaultValue(1900)]
        public int FirstYear
        {
            get
            {
                return (ViewState["FirstYear"] == null) ? 1900 : (int)ViewState["FirstYear"];
            }

            set
            {
                ViewState["FirstYear"] = value;
            }
        }
        #endregion

        #region LastYear
        [Category("Data")]
        public int LastYear
        {
            get
            {
                return (ViewState["LastYear"] == null) ? DateTime.Now.Year : (int)ViewState["LastYear"];
            }

            set
            {
                ViewState["LastYear"] = value;
            }
        }
        #endregion
        #endregion

        #region Appearance(外观)
        #region SelectCssClass
        [Category("Appearance")]
        public string SelectCssClass
        {
            get
            {
                return (ViewState["SelectCssClass"] == null) ? string.Empty : (string)ViewState["SelectCssClass"];
            }

            set
            {
                ViewState["SelectCssClass"] = value;
            }
        }
        #endregion

        #region YearTitle
        [Category("Appearance")]
        [DefaultValue("年")]
        public string YearTitle
        {
            get
            {
                return (ViewState["YearTitle"] == null) ? "年" : (string)ViewState["YearTitle"];
            }

            set
            {
                ViewState["YearTitle"] = value;
            }
        }
        #endregion

        #region MonthTitle
        [Category("Appearance")]
        [DefaultValue("月")]
        public string MonthTitle
        {
            get
            {
                return (ViewState["MonthTitle"] == null) ? "月" : (string)ViewState["MonthTitle"];
            }

            set
            {
                ViewState["MonthTitle"] = value;
            }
        }
        #endregion

        #region DayTitle
        [Category("Appearance")]
        [DefaultValue("日")]
        public string DayTitle
        {
            get
            {
                return (ViewState["DayTitle"] == null) ? "日" : (string)ViewState["DayTitle"];
            }

            set
            {
                ViewState["DayTitle"] = value;
            }
        }
        #endregion
        #endregion

        #endregion

        #region GetDate
        private void GetDate()
        {
            if(Page.IsPostBack)
            {
                string strYear = Page.Request.Form[this.ClientID + "_Year"];
                string strMonth = Page.Request.Form[this.ClientID + "_Month"];
                string strDay = Page.Request.Form[this.ClientID + "_Day"];
                ViewState["Date"] = DateTime.Parse(string.Format("{0}-{1}-{2}", strYear, strMonth, strDay));
            }
        }
        #endregion

        #region BuildJScript
        private string BuildJScript()
        {
            StringBuilder sb = new StringBuilder();
            sb.Append(" <script language="jscript"> <!-- ");
            sb.Append("function {0}_Day_Check() {{ ");
            sb.Append("var {0}_obj_Year = document.getElementById("{0}_Year"); ");
            sb.Append("var {0}_obj_Month = document.getElementById("{0}_Month"); ");
            sb.Append("if(parseInt({0}_obj_Month.value) == 2) {{ ");
            sb.Append("if(parseInt({0}_obj_Year.value) % 4 == 0) {{ ");
            sb.Append("{0}_Day_SetOptions(29); }} ");
            sb.Append("else {{ ");
            sb.Append("{0}_Day_SetOptions(28); }} }} ");
            sb.Append("else {{ ");
            sb.Append("switch(parseInt({0}_obj_Month.value)) {{ ");
            sb.Append("case 1: {0}_Day_SetOptions(31); break; ");
            sb.Append("case 3: {0}_Day_SetOptions(31); break; ");
            sb.Append("case 5: {0}_Day_SetOptions(31); break; ");
            sb.Append("case 7: {0}_Day_SetOptions(31); break; ");
            sb.Append("case 8: {0}_Day_SetOptions(31); break; ");
            sb.Append("case 10: {0}_Day_SetOptions(31); break; ");
            sb.Append("case 12: {0}_Day_SetOptions(31); break; ");
            sb.Append("case 4: {0}_Day_SetOptions(30); break; ");
            sb.Append("case 6: {0}_Day_SetOptions(30); break; ");
            sb.Append("case 9: {0}_Day_SetOptions(30); break; ");
            sb.Append("case 11: {0}_Day_SetOptions(30); break; ");
            sb.Append("default: break; }} }} }} ");
            sb.Append(" ");
            sb.Append("function {0}_Day_SetOptions({0}_Day_Count) {{ ");
            sb.Append("var {0}_obj_Day = document.getElementById("{0}_Day"); ");
            sb.Append("var {0}_Day_SelectedDay; ");
            sb.Append("if({0}_obj_Day.value == "") {{ ");
            sb.Append("{0}_Day_SelectedDay = 1; }} ");
            sb.Append("else {{ ");
            sb.Append("{0}_Day_SelectedDay = parseInt({0}_obj_Day.value); }} ");
            sb.Append("if({0}_Day_SelectedDay > {0}_Day_Count) {{ ");
            sb.Append("{0}_Day_SelectedDay = {0}_Day_Count; }} ");
            sb.Append("{0}_obj_Day.length = 0; ");
            sb.Append("for(var i = 1; i <= {0}_Day_Count; i++) {{ ");
            sb.Append("{0}_obj_Day.options.add(new Option(i, i)); }} ");
            sb.Append("{0}_obj_Day.value = {0}_Day_SelectedDay; }} ");
            sb.Append("--> </script> ");
            return string.Format(sb.ToString(), this.ClientID);
        }
        #endregion

        #region BuildHtmlElement
        private string BuildHtmlElement()
        {
            StringBuilder sb = new StringBuilder();
            sb.AppendFormat(" <select id="{0}_Year" name="{0}_Year" onchange="{0}_Day_Check();" class="{1}">", this.ClientID, this.SelectCssClass);

            for(int i = this.FirstYear; i <= this.LastYear; i++)
            {
                if(i == this.Date.Year)
                {
                    sb.AppendFormat(" <option value="{0}" selected>{0}</option>", i);
                }
                else
                {
                    sb.AppendFormat(" <option value="{0}">{0}</option>", i);
                }
            }

            sb.AppendFormat(" </select> {1}<select id="{0}_Month" name="{0}_Month" onchange="{0}_Day_Check();" class="{2}">", this.ClientID, this.YearTitle, this.SelectCssClass);

            for(int i = 1; i <= 12; i++)
            {
                if(i == this.Date.Month)
                {
                    sb.AppendFormat(" <option value="{0}" selected>{0}</option>", i);
                }
                else
                {
                    sb.AppendFormat(" <option value="{0}">{0}</option>", i);
                }
            }

            sb.AppendFormat(" </select>{1}<select id="{0}_Day" name="{0}_Day" onmouseover="{0}_Day_Check();" class="{2}">", this.ClientID, this.MonthTitle, this.SelectCssClass);

            for(int i = 1; i <= DateTime.DaysInMonth(this.Date.Year, this.Date.Month); i++)
            {
                if(i == this.Date.Day)
                {
                    sb.AppendFormat(" <option value="{0}" selected>{0}</option>", i);
                }
                else
                {
                    sb.AppendFormat(" <option value="{0}">{0}</option>", i);
                }
            }

            sb.AppendFormat(" </select>{0} ", this.DayTitle);
            return sb.ToString();
        }
        #endregion

        #region override RenderChildren
        protected override void RenderChildren(HtmlTextWriter writer)
        {
            writer.Write(this.BuildJScript());
            writer.Write(this.BuildHtmlElement());
            base.RenderChildren(writer);
        }
        #endregion
    }
}