internal static TRichString GetVisualString(TRichString Text, bool ReverseRightToLeftStrings)
{
if (!ReverseRightToLeftStrings || Text == null || Text.Length < 2)
{
return(Text);
}
BidiReference bref = new BidiReference(Text.Value);
int[] lines = { Text.Length };
int[] ReorderArray = bref.getReordering(lines);
bool ToLeft = true;
for (int i = 0; i < ReorderArray.Length; i++)
{
if (ReorderArray[i] != i)
{
ToLeft = false;
break;
}
}
if (ToLeft)
{
return(Text);
}
char[] Result = new char[ReorderArray.Length];
for (int i = 0; i < Result.Length; i++)
{
Result[i] = Text[ReorderArray[i]];
}
return(new TRichString(new string(Result)));
}
/*
* This function shapes European digits to Arabic-Indic digits
* in-place, writing over the input characters. Data is in visual
* order.
*/
private static void shapeToArabicDigitsWithContext(char[] dest, int start, int length, char digitBase, bool lastStrongWasAL)
{
digitBase -= '0'; // move common adjustment out of loop
for (int i = start + length; --i >= start;)
{
char ch = dest[i];
switch (BidiReference.Direction(ch))
{
case BidiReference.L:
case BidiReference.R:
lastStrongWasAL = false;
break;
case BidiReference.AL:
lastStrongWasAL = true;
break;
case BidiReference.EN:
if (lastStrongWasAL && ch <= '\u0039')
{
dest[i] = (char)(ch + digitBase);
}
break;
default:
break;
}
}
}
internal static bool IsLeftToRight(string Text)
{
for (int i = 0; i < Text.Length; i++)
{
sbyte l = BidiReference.Direction(Text[i]);
if (l <= BidiReference.LRO)
{
return(false);
}
if (l <= BidiReference.RLO)
{
return(true);
}
}
return(false);
}
