public ExtendFormatEventArgs(CustomFormatInfo formatInfo)
{
FormatInfo = formatInfo;
}
/// <summary>
/// Determines what to do when an Invalid Selector is found.
///
/// Returns True if we should just continue; False if we should skip this item.
/// </summary>
private bool OnInvalidSelector(string format, CustomFormatInfo info, PlaceholderInfo placeholder)
{
string invalidSelector = format.Substring(placeholder.selectorStart, placeholder.selectorLength);
string message;
switch (InvalidSelectorAction) {
case ErrorAction.ThrowError:
// Let's give a detailed description of the error:
message = FormatEx(
("Invalid Format String.\\n" +
("Could not evaluate \"{0}\": \"{1}\" is not a member of {2}.\\n" +
("The error occurs at position {3} of the following format string:\\n" + "{4}"))),
invalidSelector, info.Selector, info.CurrentType, placeholder.placeholderStart, format);
throw new ArgumentException(message, invalidSelector);
case ErrorAction.OutputErrorInResult:
// Let's put the placeholder back,
// along with the error.
// Example: {Person.Name.ABC} becomes {Person.Name.ABC:(Error: "ABC" is not a member of String)}
message = ("{" + (FormatEx("{0}:(Error: \"{1}\" is not a member of {2})", invalidSelector,
info.Selector, info.CurrentType) + "}"));
info.WriteError(message, placeholder);
return false;
case ErrorAction.Ignore:
// Allow formatting to continue!
break;
}
return true;
}
/// <summary>
/// Does the actual work.
/// </summary>
internal void FormatExInternal(CustomFormatInfo info)
{
if (info.Current == null && info.Arguments.Length >= 1) {
info.Current = info.Arguments[0];
}
// We need to store the Format and the Current items and keep them in this context
string format = info.Format;
object current = info.Current;
// ' Here is the regular expression to use for parsing the Format string:
// Static R As New Regex( _
// "{ ([0-9A-Za-z_.\[\]()]*) (?: : ( (?: (?<open>{) | (?<nest-open>}) | [^{}]+ )*? ) (?(open)(?!)) )? }" _
// , RegexOptions.IgnorePatternWhitespace Or RegexOptions.Compiled)
// { ( Selectors ) (Optnl : { Nested } or Format ) }
int lastAppendedIndex = 0;
PlaceholderInfo placeholder = null;
while (NextPlaceholder(format, lastAppendedIndex, format.Length, ref placeholder)) {
// Write the text in-between placeholders:
info.WriteRegularText(format, lastAppendedIndex, (placeholder.placeholderStart - lastAppendedIndex));
lastAppendedIndex = placeholder.placeholderStart + placeholder.placeholderLength;
// Evaluate the source by evaluating each argSelector:
info.Current = current; // Restore the current scope
//bool isFirstSelector = true; // TODO: Remove this variable if it never gets used again
int selectorIndex = -1;
foreach (string selector in placeholder.selectors) {
selectorIndex++;
info.SetSelector(selector, selectorIndex);
// Raise the ExtendCustomSource event to allow custom source evaluation:
OnExtendSourceEvent(new ExtendSourceEventArgs(info));
// Make sure that the selector has been handled:
if (!info.Handled) {
break;
}
//isFirstSelector = false;
}
// Handle errors:
if (!info.Handled) {
// If the ExtendCustomSource event wasn't handled,
// then the Selector could not be evaluated.
if (!OnInvalidSelector(format, info, placeholder)) {
continue;
}
}
string argFormat = format.Substring(placeholder.formatStart, placeholder.formatLength);
info.SetFormat(argFormat, placeholder.hasNested);
try {
// Raise the ExtendCustomFormat event to allow custom formatting:
OnExtendFormatEvent(new ExtendFormatEventArgs(info));
}
catch (Exception ex) {
// Handle errors:
OnInvalidFormat(format, info, placeholder, ex);
}
}
// Write the substring between the last bracket and the end of the string:
info.WriteRegularText(format, lastAppendedIndex, (format.Length - lastAppendedIndex));
}
/// <summary>
/// Determines what to do when an Invalid Selector is found.
/// </summary>
private void OnInvalidFormat(string format, CustomFormatInfo info, PlaceholderInfo placeholder, Exception ex)
{
string selector = format.Substring(placeholder.selectorStart, placeholder.selectorLength);
string invalidFormat = format.Substring(placeholder.formatStart, placeholder.formatLength);
string errorMessage = ex.Message;
if (ex is FormatException) {
errorMessage = FormatEx("\"{0}\" is not a valid format specifier for {1}", invalidFormat,
info.CurrentType);
}
string message;
switch (InvalidFormatAction) {
case ErrorAction.ThrowError:
// Let's give a detailed description of the error:
message = FormatEx(
("Invalid Format String.\\n" +
("Could not evaluate {{0}} because {1}.\\n" +
("The error occurs at position {2} of the following format string:\\n" + "{3}"))), selector,
errorMessage, placeholder.placeholderStart, format);
throw new ArgumentException(message, invalidFormat, ex);
case ErrorAction.OutputErrorInResult:
// Let's put the placeholder back,
// along with the error.
// Example: {Person.Birthday:x} becomes {Person.Birthday:(Error: "x" is an invalid format specifier)}
message = ("{" + (FormatEx("{0}:(Error: {1})", selector, errorMessage) + "}"));
info.WriteError(message, placeholder);
break;
case ErrorAction.Ignore:
// Allow formatting to continue!
break;
}
}
public ExtendFormatEventArgs(CustomFormatInfo formatInfo)
{
FormatInfo = formatInfo;
}
