好多朋友被ACCESS数据库在.net程序中相对路径的问题困扰,搞得每次移动程序都要去修改web.config 中数据库连接字符串的数据库路径。 好多人的web.config中的写法如下: appSettings add key="OLEDBCONNECTIONSTRING" value="Provider=Microsoft.Jet.OLEDB.4.
好多朋友被ACCESS数据库在.net程序中相对路径的问题困扰,搞得每次移动程序都要去修改web.config
中数据库连接字符串的数据库路径。
好多人的web.config中的写法如下:
程序中这样写:
MyConn = new OleDbConnection(System.Configuration.ConfigurationManager.AppSettings["OLEDBCONNECTIONSTRING"]); //注释一下:VS2005和VS2003中的ConfigurationSettings写法不一样,具体区别自己查吧
这样程序运行时经常提示诸如以下的错误:
'C:\WINDOWS\system32\~\App_Data\Data.mdb'不是一个有效的路径。 确定路径名称拼写是否正确,以及是否连接到文件存放的服务器。 Data Source=~\App_Data\Data.mdb
就算用绝对路径正确,那么移植程序时还要去修改web.config,所以比较麻烦。
也有在web.config中使用象ASP那样的Server.MapPath取数据库路径的,但web.config不认识Server.MapPath,此方法也行不通。
后来通过摸索、参考其它程序,总结出如下方法,可以方便的移植程序路径而不必再去修改ACCESS数据库路径。
我在web.config中的写法如下:
程序中的数据访问类中我把"SQLConnString"和"dbPath"取出来连接成一个字符串"CONN_STRING_NON_DTC"
public static readonly string CONN_STRING_NON_DTC = System.Configuration.ConfigurationManager.AppSettings["SQLConnString"].ToString() + System.Web.HttpContext.Current.Server.MapPath(ConfigurationManager.AppSettings["dbPath"]) + ";";
http://blog.csdn.net/zhangqiao840405/archive/2009/07/07/4328370.aspx

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