public static string EscapeUri(string input)
{
StringBuilder sb = new StringBuilder();
int start = 0;
for (int i = 0; i < input.Length; i++)
{
char c = input [i];
if (c < 32 || c > 127)
{
continue;
}
bool preserve = false;
switch (c)
{
case '&':
case '<':
case '>':
case '"':
case '\'':
preserve = true;
break;
default:
preserve = HtmlUriEscape.IsExcludedCharacter(c);
break;
}
if (preserve)
{
sb.Append(EscapeString(input.Substring(start, i - start)));
sb.Append(c);
start = i + 1;
}
}
if (start < input.Length)
{
sb.Append(EscapeString(input.Substring(start)));
}
return(sb.ToString());
}
public override void WriteAttributeString(string prefix, string localName, string nsURI, string value)
{
writer.Write(' ');
if (prefix != null && prefix.Length != 0)
{
writer.Write(prefix);
writer.Write(":");
}
writer.Write(localName);
if (nonHtmlDepth >= 0)
{
writer.Write("=\"");
openAttribute = true;
WriteFormattedString(value);
openAttribute = false;
writer.Write('\"');
return;
}
string attribute = localName.ToUpper(CultureInfo.InvariantCulture);
string element = ((string)elementNameStack.Peek()).ToLower(CultureInfo.InvariantCulture);
if (attribute == "SELECTED" && element == "option" ||
attribute == "CHECKED" && element == "input")
{
return;
}
writer.Write("=\"");
openAttribute = true;
// URI attribute should be escaped.
string attrName = null;
string [] attrNames = null;
switch (element)
{
case "q":
case "blockquote":
case "ins":
case "del":
attrName = "cite";
break;
case "form":
attrName = "action";
break;
case "a":
case "area":
case "link":
case "base":
attrName = "href";
break;
case "head":
attrName = "profile";
break;
case "input":
attrNames = new string [] { "src", "usemap" };
break;
case "img":
attrNames = new string [] { "src", "usemap", "longdesc" };
break;
case "object":
attrNames = new string [] { "classid", "codebase", "data", "archive", "usemap" };
break;
case "script":
attrNames = new string [] { "src", "for" };
break;
}
if (attrNames != null)
{
string attr = localName.ToLower(CultureInfo.InvariantCulture);
foreach (string a in attrNames)
{
if (a == attr)
{
value = HtmlUriEscape.EscapeUri(value);
break;
}
}
}
else if (attrName != null && attrName == localName.ToLower(CultureInfo.InvariantCulture))
{
value = HtmlUriEscape.EscapeUri(value);
}
WriteFormattedString(value);
openAttribute = false;
writer.Write('\"');
}
