public static SwapInfo Swap(this TextDocument document, int xStart, int xLength, int yStart, int yLength)
{
if (xStart > yStart)
{
(xStart, yStart) = (yStart, xStart);
(xLength, yLength) = (yLength, xLength);
}
if (xStart + xLength > yStart)
{
throw new ArgumentException();
}
var xText = document.GetText(xStart, xLength);
var yText = document.GetText(yStart, yLength);
var intervalText = document.GetText(xStart + xLength, yStart - (xStart + xLength));
var newTest = yText + intervalText + xText;
var offsetChangeMap = new OffsetChangeMap()
{
new OffsetChangeMapEntry(yStart, yLength, xLength),
new OffsetChangeMapEntry(xStart, xLength, yLength),
};
document.Replace(xStart, newTest.Length, newTest, offsetChangeMap);
return(SwapInfo.CreateFrom(new SwapInfo.SwapNode(xStart, xText), new SwapInfo.SwapNode(yStart, yText)));
}
static public bool TryCreateSwapInfo(this DocumentChangeEventArgs e, out SwapInfo?info)
{
info = SwapInfo.CreateFrom(e);
return(info != null);
}
static public SwapInfo?TryCreateSwapInfo(this DocumentChangeEventArgs e)
{
return(SwapInfo.CreateFrom(e));
}