/// <summary>
/// Cleans up a string to make a legal url part
/// </summary>
/// <param name="urlName">The URL part text.</param>
/// <param name="punctuationReplacement">The text with which to replace invalid characters</param>
/// <param name="maxLength">The maximum length of the URL part</param>
/// <returns>The cleaned URL part name</returns>
private static string MakeUrlSafe(string urlName, string punctuationReplacement = "-", int maxLength = 50)
{
const string IllegalCharacters = "#%&*{}\\:<>?/+'.";
const string UnwantedCharacters = ";,\"+!'{}[]()^$*";
if (urlName == null)
{
urlName = string.Empty;
}
urlName = urlName.Normalize(NormalizationForm.FormD);
var outUrl = new StringBuilder(urlName.Length);
var i = 0;
foreach (char c in urlName)
{
if (!IllegalCharacters.Contains(c.ToString()))
{
// can't have leading .. or trailing .
if (!((i <= 0 || i == urlName.Length) && c == '.'))
{
if (c == ' ' || UnwantedCharacters.Contains(c.ToString()))
{
// replace spaces, commas and semicolons
outUrl.Append(punctuationReplacement);
}
else if (CharUnicodeInfo.GetUnicodeCategory(c) != UnicodeCategory.NonSpacingMark)
{
outUrl.Append(c);
}
}
}
i++;
if (i >= maxLength)
{
break;
}
}
string result = outUrl.ToString();
// replace double replacements
string doubleReplacement = punctuationReplacement + punctuationReplacement;
if (result.Contains(doubleReplacement))
{
result = result.Replace(doubleReplacement, punctuationReplacement);
// once more for triples
result = result.Replace(doubleReplacement, punctuationReplacement);
}
// Global.asax Application_BeginRequest checks for these values and will try to redirect to the non-existent page
if (result.EndsWith("install", StringComparison.CurrentCultureIgnoreCase) ||
result.EndsWith("installwizard", StringComparison.CurrentCultureIgnoreCase))
{
result = result.Substring(0, result.Length - 1);
}
return(result);
}
/// <summary> /// Replaces unsafe symbols with dashes /// </summary> /// <param name="input">String to sanitize</param> /// <returns>Sanitized string</returns> public static string Sanitize(string input) => IllegalCharacters.Aggregate(input, (current, bad) => current.Replace(bad, '-'));