web程序中获取应用程序系统变量的方法（ For.net 1.1)

获取系统变量在.net 的web应用程序中的确是非常方便，比如获取 "http://ap2:8080/"或者"http://10.0.0.1/mypplication/"等诸如此类的系统变量。
注：本文主要是针对.net Framework 1.0、1.1的情况，因为.net 2.0的命名空间已经发生了很大的变化，在后面的文章中将会专门加以介绍 。

为描述方便，先新建一aspx文件，前台文件如下：

< body MS_POSITIONING ="GridLayout" >
< form id ="Form2" method ="post" runat ="server" >
< FONT face ="宋体" >
< asp:Button id ="btn_Page" style ="Z-INDEX:101;LEFT:8px;POSITION:absolute;TOP:16px" runat ="server"
Text ="通过Page获取" ></ asp:Button >
< asp:Label id ="lbInfo1" style ="Z-INDEX:102;LEFT:48px;POSITION:absolute;TOP:56px" runat ="server" ></ asp:Label >
< asp:Button id ="btn_ServerVal" style ="Z-INDEX:103;LEFT:520px;POSITION:absolute;TOP:16px"
runat ="server" Text ="通过ServerVariables获取" ></ asp:Button >
< asp:Label id ="lbInfo2" style ="Z-INDEX:104;LEFT:48px;POSITION:absolute;TOP:80px" runat ="server" ></ asp:Label >
< asp:Label id ="lbInfo3" style ="Z-INDEX:105;LEFT:48px;POSITION:absolute;TOP:104px" runat ="server" ></ asp:Label >
< asp:Button id ="btn_Cintext" style ="Z-INDEX:106;LEFT:280px;POSITION:absolute;TOP:16px"
runat ="server" Text ="通过Context获取" ></ asp:Button ></ FONT >
</ form >
</ body >

第一种方法，直接在在页面中获取。利用Page.Request命名空间。

private void btn_Page_Click( object sender,System.EventArgse)
... {
this .lbInfo2.Text = "" ;
this .lbInfo3.Text = "" ;
this .lbInfo1.Text = Page.Request.ApplicationPath + " <br/> "
+ Page.Request.CurrentExecutionFilePath + " <br/> "
+ Page.Request.UserHostAddress + " <br/> "
+ Page.Request.Url.Host + " <br/> "
+ Page.Request.RawUrl + " <br/> "
+ Page.Request.UserHostName + " <br/> "
+ Page.Request.Url.HostNameType + " <br/> "
+ Page.Request.Url.Port + " <br/> "
+ Page.Request.UrlReferrer.Host + " <br/> "
+ Page.Request.Url.LocalPath + " <br/> "
+ Page.Request.Url.Authority + " <br/> "
+ Page.Request.Url.UserInfo + " <br/> "
+ " <br/> " ;

}

第二种方法：在非Web项目中用Context的Request方法。

private void btn_Cintext_Click( object sender,System.EventArgse)
... {
this .lbInfo1.Text = "" ;
this .lbInfo3.Text = "" ;
this .lbInfo2.Text =
System.Web.HttpContext.Current.Server.MachineName + " <br/> "
+ System.Web.HttpContext.Current.Request.ApplicationPath + " <br/> "
+ System.Web.HttpContext.Current.Request.CurrentExecutionFilePath + " <br/> "
+ System.Web.HttpContext.Current.Request.RawUrl + " <br/> "
+ System.Web.HttpContext.Current.Request.Url + " <br/> "
+ System.Web.HttpContext.Current.Request.UserHostAddress + " <br/> "
+ System.Web.HttpContext.Current.Request.UserHostName + " <br/> "
+ System.Web.HttpContext.Current.Request.RequestType + " <br/> "
+ System.Web.HttpContext.Current.Request.UrlReferrer.Host + " <br/> "
+ System.Web.HttpContext.Current.Request.UrlReferrer.HostNameType + " <br/> "
+ System.Web.HttpContext.Current.Request.Path + " <br/> "
+ System.Web.HttpContext.Current.Request.Url.Port + " <br/> "
+ System.Web.HttpContext.Current.Request.Url.IsDefaultPort.ToString() + " <br/> "
+ System.Web.HttpContext.Current.Request.Url.IsFile.ToString() + " <br/> "
+ System.Web.HttpContext.Current.Request.Url.LocalPath + " <br/> "
+ " <br/> " ;

}

第三种方法：可以从Request.ServerVariables的集合中获取 。获取的变量也最全。

private void btn_ServerVal_Click( object sender,System.EventArgse)
... {

this .lbInfo1.Text = "" ;
this .lbInfo2.Text = "" ;
int loop1,loop2;
System.Collections.Specialized.NameValueCollectioncoll;

// 以下两种方式均可
// coll=Page.Request.ServerVariables;
coll = System.Web.HttpContext.Current.Request.ServerVariables;
this .lbInfo3.Text = "" ;
// Getnamesofallkeysintoastringarray.
String[]arr1 = coll.AllKeys;
for (loop1 = 0 ;loop1 < arr1.Length;loop1 ++ )
... {
this .lbInfo3.Text += ( " Key: " + arr1[loop1] + " <br> " );
String[]arr2 = coll.GetValues(arr1[loop1]);
for (loop2 = 0 ;loop2 < arr2.Length;loop2 ++ )
... {
this .lbInfo3.Text += ( " Value " + loop2 + " : " + Server.HtmlEncode(arr2[loop2]) + " <br> " );
}
}
}

亦可用于 Web service

注意，以上方法获取IP未必真实。