/// <summary>
/// Extend the string constructor with a string.Format like syntax.
/// </summary>
/// <param name="args"></param>
/// <param name="placing"></param>
/// <returns></returns>
private static string FormatWith(EllipsisPlacement placing,
params object[] args)
{
string formatString;
switch (placing)
{
case EllipsisPlacement.None:
formatString = "{0}{1}";
break;
case EllipsisPlacement.Left:
formatString = "...{0}{1}";
break;
case EllipsisPlacement.Center:
formatString = "{0}...{1}";
break;
case EllipsisPlacement.Right:
formatString = "{0}{1}...";
break;
default:
throw new ArgumentOutOfRangeException(placing.ToString());
}
return(string.Format(CultureInfo.InvariantCulture, formatString, args));
}
// Sets Text to a substring of LongText based on _placement and _curLen.
private void CalcText()
{
if (LongText == null)
{
switch (EllipsisPlacement)
{
case EllipsisPlacement.Left:
case EllipsisPlacement.Center:
case EllipsisPlacement.Right:
case EllipsisPlacement.Path:
SetText(LongText);
break;
}
return;
}
switch (EllipsisPlacement)
{
case EllipsisPlacement.Right:
SetText(LongText.Substring(0, _curLen) + "\u2026");
break;
case EllipsisPlacement.Center:
int firstLen = _curLen / 2;
int secondLen = _curLen - firstLen;
SetText(LongText.Substring(0, firstLen) + "\u2026" + LongText.Substring(LongText.Length - secondLen));
break;
case EllipsisPlacement.Left:
int start = LongText.Length - _curLen;
SetText("\u2026" + LongText.Substring(start));
break;
case EllipsisPlacement.Path:
var sb = new StringBuilder(_curLen + 1);
PathCompactPathEx(sb, LongText, _curLen, 0);
SetText(sb.ToString());
break;
default:
throw new Exception("Unexpected switch value: " + EllipsisPlacement.ToString());
}
}
/// <summary>
/// Compute the text to display (with ellipsis) that fits the ActualWidth of the container
/// </summary>
/// <param name="inputString">Input string to measure whether it fits into container width or not.</param>
/// <param name="constraint">ActualWidth restriction by container element (eg.: Grid)</param>
/// <param name="placement"></param>
/// <param name="ctrl"></param>
/// <returns></returns>
private static Tuple <string, Size> GetTrimmedPath(string inputString,
Size constraint,
EllipsisPlacement placement,
Control ctrl)
{
Size size = new Size();
string filename = string.Empty;
string directory = string.Empty;
if (constraint.Width != double.PositiveInfinity)
{
size.Width = constraint.Width;
}
if (constraint.Height != double.PositiveInfinity)
{
size.Height = constraint.Height;
}
switch (placement)
{
// We don't want no ellipses to be shown for a string shortener
case EllipsisPlacement.None:
size = MeasureString(inputString, ctrl);
return(new Tuple <string, Size>(inputString, size));
// Try to show a nice ellipses somewhere in the middle of the string
case EllipsisPlacement.Center:
try
{
if (string.IsNullOrEmpty(inputString) == false)
{
if (inputString.Contains(string.Empty + System.IO.Path.DirectorySeparatorChar))
{
// Lets try to display the file name with priority
filename = System.IO.Path.GetFileName(inputString);
directory = System.IO.Path.GetDirectoryName(inputString);
}
else
{
// Cut this right in the middle since it does not seem to hold path info
int len = inputString.Length;
int firstLen = inputString.Length / 2;
filename = inputString.Substring(0, firstLen);
if (inputString.Length >= (firstLen + 1))
{
directory = inputString.Substring(firstLen);
}
}
}
else
{
size = MeasureString(string.Empty, ctrl);
return(new Tuple <string, Size>(inputString, size));
}
}
catch (Exception)
{
directory = inputString;
filename = string.Empty;
}
break;
case EllipsisPlacement.Left:
directory = inputString;
filename = string.Empty;
break;
case EllipsisPlacement.Right:
directory = string.Empty;
filename = inputString;
break;
default:
throw new ArgumentOutOfRangeException(placement.ToString());
}
double fudgeValue = 3.0;
bool widthOK = false;
int indexString = 0;
string path = inputString;
bool changedWidth = false;
if (placement == EllipsisPlacement.Left)
{
indexString = 1;
}
do
{
path = FormatWith(placement, directory, filename);
size = MeasureString(path, ctrl);
widthOK = (size.Width + fudgeValue) < constraint.Width;
if (widthOK == false)
{
if (directory.Length == 0)
{
if (filename.Length > 0)
{
changedWidth = true;
filename = filename.Substring(indexString, filename.Length - 1);
}
else
{
size = MeasureString(string.Empty, ctrl);
return(new Tuple <string, Size>(inputString, size));
}
}
else
{
changedWidth = true;
directory = directory.Substring(indexString, directory.Length - 1);
}
}
}while (widthOK == false);
size.Width += fudgeValue;
if (changedWidth == false)
{
return(new Tuple <string, Size>(inputString, size));
}
return(new Tuple <string, Size>(path, size));
}
/// <summary>Initializes a new instance of the <see cref="TextBoxWithEllipsis"/> class.</summary>
public TextBoxWithEllipsis()
{
// Initialize inherited stuff as desired.
this.IsReadOnlyCaretVisible = true;
// Initialize stuff added by this class
this.IsEllipsisEnabled = true;
this.UseLongTextForToolTip = true;
this.FudgePix = 3.0;
this.placement = EllipsisPlacement.Right;
this.internalEnabled = true;
this.LayoutUpdated += this.TextBoxWithEllipsisLayoutUpdated;
this.SizeChanged += this.TextBoxWithEllipsisSizeChanged;
}
