如何获取相对uri的绝对uri？

Question

我有一个页面，其相对路径是“~/pages/mypage.aspx”。

我尝试使用 VirtualPathUtility.ToAbsolute(@"~/pages/mypage.aspx") 希望获得绝对 uri，但它只返回相同的相对路径。

如何从相对 uri 中获取绝对 uri？

谢谢，

Answer 1

我用了这个方法：

private static string GetAbsoluteUrl(string relativeUrl)
    {
        var applicationUrl = String.Empty;

        // remove ~
        if (relativeUrl.StartsWith("~"))
        {
            applicationUrl = relativeUrl.Substring(1);
        }

        applicationUrl = (HttpContext.Current.Request.ApplicationPath + applicationUrl)
            .Replace("//", "/");

        var baseUrl = String.Format("{0}://{1}:{2}",
                                    HttpContext.Current.Request.Url.Scheme,
                                    HttpContext.Current.Request.Url.Host,
                                    HttpContext.Current.Request.Url.Port);

        return baseUrl + applicationUrl;
    }

Answer 2

 public static string ResolveUrl(string originalUrl)
    {
        if (originalUrl == null)
            return null;

        // *** Absolute path - just return
        if (originalUrl.IndexOf("://") != -1)
            return originalUrl;

        // *** Fix up image path for ~ root app dir directory
        if (originalUrl.StartsWith("~"))
        {
            string newUrl = "";
            if (HttpContext.Current != null)
                newUrl = HttpContext.Current.Request.ApplicationPath +
                      originalUrl.Substring(1).Replace("//", "/");
            else
                // *** Not context: assume current directory is the base directory
                throw new ArgumentException("Invalid URL: Relative URL not allowed.");

            // *** Just to be sure fix up any double slashes
            return newUrl;
        }

        return originalUrl;
    }

摘自http://www.west-wind.com/weblog/posts/154812 .aspx