public static IEnumerator GetCDNWWW(string url, System.Action <WWW> retWWW, bool bAddStamp = true) { string firstUrl = url; if (bAddStamp) { firstUrl = AddTimestampToUrl(url); } WWW wwwOrg = new WWW(firstUrl); yield return(wwwOrg); if (string.IsNullOrEmpty(wwwOrg.error) || string.IsNullOrEmpty(PlatformHelper.GetCDNOrgUrl()) || string.IsNullOrEmpty(PlatformHelper.GetResDonwloadUrl())) { retWWW(wwwOrg); yield break; } string replaceUrl = url.Replace(PlatformHelper.GetCDNOrgUrl(), PlatformHelper.GetCDNReplaceUrl()); WWW wwwReplace = new WWW(replaceUrl); yield return(wwwReplace); if (string.IsNullOrEmpty(wwwReplace.error) || string.IsNullOrEmpty(PlatformHelper.GetCDNReplaceUrl2())) { retWWW(wwwReplace); yield break; } string replaceUrl2 = url.Replace(PlatformHelper.GetCDNOrgUrl(), PlatformHelper.GetCDNReplaceUrl2()); WWW wwwReplace2 = new WWW(replaceUrl2); yield return(wwwReplace2); retWWW(wwwReplace2); }