public override async Task ProcessAsync(TagHelperContext context, TagHelperOutput output)
{
if (Url == null)
{
return;
}
output.CopyHtmlAttribute(UrlAttributeName, context);
Microsoft.AspNetCore.Mvc.IUrlHelper urlHelper = _urlHelperFactory.GetUrlHelper(ViewContext);
UrlUtils.FromRelative(urlHelper.Content(Url), out PathString path, out QueryString query, out _);
string url = null;
var n = _bundleManagerFactory.Instances.Count;
for (var i = 0; i < n; i++)
{
if ((url = await _bundleManagerFactory.Instances[i].TryGenerateUrlAsync(path, query, ViewContext.HttpContext)) != null)
{
break;
}
}
if (url != null)
{
var index = output.Attributes.IndexOfName(UrlAttributeName);
TagHelperAttribute existingAttribute = output.Attributes[index];
output.Attributes[index] = new TagHelperAttribute(existingAttribute.Name, url, existingAttribute.ValueStyle);
}
}
public static PathMap FromUrl(Microsoft.AspNetCore.Hosting.IHostingEnvironment env
, Microsoft.AspNetCore.Mvc.IUrlHelper urlHelper
, string baseSrc)
{
if (baseSrc.StartsWith("data:"))
{
throw new System.ArgumentException("data: cannot be transformed into URL.");
}
PathMap pmr = new PathMap();
pmr.Original = baseSrc;
int argsPos = baseSrc.IndexOf("?");
int hashPos = baseSrc.IndexOf("#");
pmr.QueryString = "";
pmr.Hash = "";
if (hashPos != -1)
{
pmr.Hash = baseSrc.Substring(hashPos);
baseSrc = baseSrc.Substring(0, hashPos);
}
if (argsPos != -1)
{
pmr.QueryString = baseSrc.Substring(argsPos);
baseSrc = baseSrc.Substring(0, argsPos);
}
string imageVirtualPath = null;
if (
baseSrc.StartsWith("http:", System.StringComparison.InvariantCultureIgnoreCase) ||
baseSrc.StartsWith("https:", System.StringComparison.InvariantCultureIgnoreCase))
{
pmr.Canonical = baseSrc;
string domain = urlHelper.ActionContext.HttpContext.Request.Scheme + "://"
+ urlHelper.ActionContext.HttpContext.Request.Host.Value;
if (baseSrc.StartsWith(domain, System.StringComparison.InvariantCultureIgnoreCase))
{
baseSrc = baseSrc.Substring(domain.Length);
}
else
{
pmr.PhysicalApplicable = false;
System.Uri uri = new System.Uri(baseSrc, System.UriKind.Absolute);
pmr.Absolute = uri.AbsolutePath;
}
}
if (baseSrc.StartsWith("~"))
{
imageVirtualPath = urlHelper.Content(baseSrc); // To Virtual Path
}
else if (baseSrc.StartsWith("/"))
{
imageVirtualPath = baseSrc;
}
else if (
!baseSrc.StartsWith("http:", System.StringComparison.InvariantCultureIgnoreCase) &&
!baseSrc.StartsWith("https:", System.StringComparison.InvariantCultureIgnoreCase)
)
{
imageVirtualPath = urlHelper.ActionContext.HttpContext.Request.PathBase.Value;
imageVirtualPath += urlHelper.ActionContext.HttpContext.Request.Path.Value;
if (!string.IsNullOrEmpty(imageVirtualPath))
{
if (!imageVirtualPath.EndsWith("/"))
{
int li = imageVirtualPath.LastIndexOf('/');
if (li != -1)
{
imageVirtualPath = imageVirtualPath.Substring(0, li + 1);
}
System.Console.WriteLine(imageVirtualPath);
}
//if (!string.IsNullOrEmpty(imageVirtualPath))
// imageVirtualPath += "/";
}
imageVirtualPath += baseSrc;
}
pmr.Absolute = imageVirtualPath;
if (pmr.Canonical == null)
{
pmr.Canonical = urlHelper.ActionContext.HttpContext.Request.Scheme
+ "://"
+ urlHelper.ActionContext.HttpContext.Request.Host.Value;
pmr.Canonical += pmr.Absolute;
// System.Uri bas = new System.Uri(HttpContext.Request.Scheme + "://" + HttpContext.Request.Host.Value, System.UriKind.Absolute);
// System.Uri canonicalUrl = new System.Uri(bas, imagePhysicalPath);
}
if (pmr.PhysicalApplicable && env != null)
{
string rootPath = urlHelper.Content("~"); // To Virtual Path
if (imageVirtualPath.StartsWith(rootPath, System.StringComparison.InvariantCultureIgnoreCase))
{
pmr.Physical = imageVirtualPath.Substring(rootPath.Length);
}
else
{
pmr.Physical = imageVirtualPath;
}
if (pmr.Physical.StartsWith('/'))
{
pmr.Physical = pmr.Physical.Substring(1);
}
// https://stackoverflow.com/questions/40001242/aspnetcore-get-path-to-wwwroot-in-taghelper
// this.HostingEnvironment.WebRootPath // d.h: /wwwroot
// this.HostingEnvironment.ContentRootPath // d.h: /wwwroot/..
pmr.Physical = pmr.Physical.Replace('/', System.IO.Path.DirectorySeparatorChar);
pmr.Physical = System.IO.Path.Combine(env.WebRootPath, pmr.Physical);
pmr.Physical = System.IO.Path.GetFullPath(pmr.Physical);
}
return(pmr);
}