asp.net中的n種path

在web伺服器端開發中經常會遇到各種不同形式的path，而且經常記不清楚如何擷取到某種特定格式，今天抽了點時間把常用的path擷取方法與格式做了一個簡單的對照表，以備日後查用。
Request擷取的資訊
Request.AppRelativeCurrentExecutionFilePath                  ~/SysOption/BillingSetup1.aspx
Request.ApplicationPath                                                 /
Request.CurrentExecutionFilePath                                   /SysOption/BillingSetup1.aspx
Request.FilePath                                                            /SysOption/BillingSetup1.aspx
Request.Path                                                                /SysOption/BillingSetup1.aspx
Request.PathInfo                                                          什麼都沒有（待測其他用法）
Request.PhysicalApplicationPath                                      D:\VssWorkFolder\British_School_MIS\src\WebSite\
Request.PhysicalPath                                                      D:\VssWorkFolder\British_School_MIS\src\WebSite\SysOption\BillingSetup1.aspx
Request.UserHostAddress                                              192.168.1.6
Request.UserHostName                                                  192.168.1.6
Request.Url.ToString()                                                    http://192.168.1.6/SysOption/BillingSetup1.aspx?x=d
Request.UrlReferrer                                                        Null 參考或者跳轉源頁面地址        

Request.ServerVariables集合中擷取到的相關資訊:
左列是伺服器變數名，右側是值，值是通過Request.ServerVariables[伺服器變數名]擷取的
APPL_MD_PATH : /LM/W3SVC/894523/Root
APPL_PHYSICAL_PATH : D:\VssWorkFolder\British_School_MIS\src\WebSite\
INSTANCE_META_PATH : /LM/W3SVC/894523
LOCAL_ADDR : 192.168.1.6
PATH_INFO : /SysOption/BillingSetup1.aspx
PATH_TRANSLATED : D:\VssWorkFolder\British_School_MIS\src\WebSite\SysOption\BillingSetup1.aspx
REMOTE_ADDR : 192.168.1.6
REMOTE_HOST : 192.168.1.6
SCRIPT_NAME : /SysOption/BillingSetup1.aspx
SERVER_NAME : 192.168.1.6
URL : /SysOption/BillingSetup1.aspx

Request.ServerVariables是一個很強大的工具，可以協助我們擷取很多client和web宿主的資訊，有興趣的朋友可以通過以下代碼看看它到底包含什麼資訊        foreach (string s in Request.ServerVariables)
        {
            Response.Write(s + "  :  " + Request.ServerVariables[s] + "<br /><br />");
        }

path轉換
1.轉換為伺服器端路徑（Server.MapPath）
web伺服器端開發設計一個有趣的問題就是，地址轉換。比如http地址/images/a.txt，如果你想在伺服器端通過io讀取這個檔案，就得有這個檔案的“本機地址（形如c:\windows\system32\xx.dll）”,這時Server.MapPath就很有用了
Response.Write(Request.MapPath(Request.Path));        輸出為 D:\VssWorkFolder\British_School_MIS\src\WebSite\SysOption\BillingSetup1.aspx
2.轉換為http地址（Page.ResolveClientUrl Page.ResolveUrl）
Response.Write(Page.ResolveClientUrl("~/a/a.jpg"));      輸出為 ../a/a.jpg
Response.Write(Page.ResolveUrl("~/a/a.jpg"));              輸出為 /a/a.jpg