Ajax使用心得

1、先在程序load的时候注册类到Ajax
如：private void Page_Load(object sender, EventArgs e) 
  { 
        Ajax.Utility.RegisterTypeForAjax(typeof(BD0047));        //将类BD0047加到Ajax中
}
2、在要在前调用的方法前加 [AjaxMethod()]
如：[AjaxMethod()]
  public int CountIssueDays(string strIssueDate,string strMaturityDate)
  { 
   int retValue=0;
   if(strIssueDate!="" && strMaturityDate!="")
   {  
    string []strStartDate=new string[]{""};
    string []strEndDate=new string[]{""};
    //将日期分割成数组
    int placeIssueDate=strIssueDate.IndexOf("-",0,strIssueDate.Length);           //判断日期中是否有'-'号
    int placeMaturityDate=strMaturityDate.IndexOf("-",0,strMaturityDate.Length);  //判断日期中是否有'-'号
    if(placeIssueDate==0)
    {
     strStartDate=new string[]{strIssueDate.Substring(0,4),strIssueDate.Substring(4,2),strIssueDate.Substring(6,2)};
           
    }
    else
    {
     strStartDate=strIssueDate.Split('-');
    }
    if(placeMaturityDate==0)
    {
     strEndDate=new string[]{strMaturityDate.Substring(0,4),strMaturityDate.Substring(4,2),strMaturityDate.Substring(6,2)};
    }
    else
    {
     strEndDate=strMaturityDate.Split('-');
    }
               
    TimeSpan tsIssueDays=new TimeSpan();
 
    DateTime dtIssueDate=new DateTime(int.Parse(strStartDate[0]),int.Parse(strStartDate[1]),int.Parse(strStartDate[2]));
    DateTime dtMaturityDate=new DateTime(int.Parse(strEndDate[0]),int.Parse(strEndDate[1]),int.Parse(strEndDate[2]));
    tsIssueDays=dtMaturityDate-dtIssueDate;
                
    retValue=tsIssueDays.Days + 1;
   }
   return retValue;
  }
3、在HTML代码的最底部</Body>前加入JavaScript
var strIssueDays = document.getElementById("txtIssueDays_txtIssueDays_EditBox"); //发行天数
var strMaturityDate = document.getElementById("txtMaturityDate_txtMaturityDate_EditBox"); //到期日
var strIssueDate = document.getElementById("txtIssueDate_txtIssueDate_EditBox"); //发行日
获得页面上的控件的ID，以便把它的Value值传进要调用的方法中
4、在前台HTML中用JavaScript调用后台的方法
//计算发行天数 function CountIssueDays()
{
var returnIssueDays=BD0047.CountIssueDays(strIssueDate.value,strMaturityDate.value); strIssueDays.value=returnIssueDays.value;
}
5、再用下面语句触发事件执行Ajax去调用后台的方法
如
■先获得触发控件的ID
var strIssueDays = document.getElementById("txtIssueDays_txtIssueDays_EditBox"); //发行天数
var strMaturityDate = document.getElementById("txtMaturityDate_txtMaturityDate_EditBox"); //到期日
■触发计算发行天数事件
strIssueDate.attachEvent('onblur',function(){CountIssueDays();}); 
strMaturityDate.attachEvent('onblur',function(){CountIssueDays();});
■注意事项：
1、要在程序load的时候注册类到Ajax
2、要把Ajax引进程序中，再用Using Ajax把它引用进程序中
3、要在网站总目录下有一个Web.config配置文件
用文件编辑器打开它，
在里面的<system.web>下加入以下代码
   <httpHandlers>
      <add verb="POST,GET" path="ajax/*.ashx" type="Ajax.PageHandlerFactory, Ajax" />
    </httpHandlers>