public static string Escape(string input, bool inCharGroup = false)
{
if (input == null)
{
throw new ArgumentNullException(nameof(input));
}
for (int i = 0; i < input.Length; i++)
{
CharEscapeMode mode = GetEscapeMode(input[i], inCharGroup);
if (mode != CharEscapeMode.None)
{
var sb = new StringBuilder();
char ch = input[i];
int lastPos;
sb.Append(input, 0, i);
do
{
switch (mode)
{
case CharEscapeMode.AsciiHexadecimal:
{
sb.Append(@"\x");
sb.Append(((int)ch).ToString("X2", CultureInfo.InvariantCulture));
break;
}
case CharEscapeMode.Backslash:
{
sb.Append('\\');
sb.Append(ch);
break;
}
case CharEscapeMode.Bell:
{
sb.Append(@"\a");
break;
}
case CharEscapeMode.CarriageReturn:
{
sb.Append(@"\r");
break;
}
case CharEscapeMode.Escape:
{
sb.Append(@"\e");
break;
}
case CharEscapeMode.FormFeed:
{
sb.Append(@"\f");
break;
}
case CharEscapeMode.Linefeed:
{
sb.Append(@"\n");
break;
}
case CharEscapeMode.VerticalTab:
{
sb.Append(@"\v");
break;
}
case CharEscapeMode.Tab:
{
sb.Append(@"\t");
break;
}
}
i++;
lastPos = i;
while (i < input.Length)
{
ch = input[i];
mode = GetEscapeMode(ch, inCharGroup);
if (mode != CharEscapeMode.None)
{
break;
}
i++;
}
sb.Append(input, lastPos, i - lastPos);
} while (i < input.Length);
return(sb.ToString());
}
}
return(input);
}
private void Append(char ch, CharEscapeMode mode)
{
switch (mode)
{
case CharEscapeMode.AsciiHexadecimal:
AppendAsciiHexadecimal((int)ch);
break;
case CharEscapeMode.Backslash:
AppendBackslash(ch);
break;
case CharEscapeMode.Bell:
AppendBackslash('a');
break;
case CharEscapeMode.CarriageReturn:
AppendBackslash('r');
break;
case CharEscapeMode.Escape:
AppendBackslash('e');
break;
case CharEscapeMode.FormFeed:
AppendBackslash('f');
break;
case CharEscapeMode.Linefeed:
AppendBackslash('n');
break;
case CharEscapeMode.VerticalTab:
AppendBackslash('v');
break;
case CharEscapeMode.Tab:
AppendBackslash('t');
break;
}
}
