/// <summary>
/// Converts a long filename to a short 8.3 filename.
/// </summary>
/// <param name="fileName">The long filename.</param>
/// <returns>The converted 8.3 filename. If the filename includes a
/// starting path then this is stripped from the returned value.</returns>
public static string Convert(string fileName, NameExists getFileNameExists)
{
if (fileName == null) {
return String.Empty;
}
// Remove invalid characters.
string fileNameWithoutExtension = Path.GetFileNameWithoutExtension(fileName);
string extension = Path.GetExtension(fileName);
StringBuilder shortFileName = new StringBuilder();
int length = 0;
foreach (char ch in fileNameWithoutExtension) {
if (IsValidShortFileNameChar(ch)) {
shortFileName.Append(ch);
++length;
}
}
// Get truncated extension.
if (extension.Length > MaximumFileNameExtensionLength) {
extension = extension.Substring(0, MaximumFileNameExtensionLength);
}
// Truncate filename without extension if it is too long.
if (length > MaximumFileNameWithoutExtensionLength) {
shortFileName.Remove(FileNameWithoutExtensionTruncatedLength, length - FileNameWithoutExtensionTruncatedLength);
return GetTruncatedFileName(shortFileName.ToString(), extension, getFileNameExists);
}
// Add extension.
shortFileName.Append(extension);
return shortFileName.ToString().ToUpperInvariant();
}
/// <summary>
/// Converts a long filename to a short 8.3 filename.
/// </summary>
/// <param name="fileName">The long filename.</param>
/// <returns>The converted 8.3 filename. If the filename includes a
/// starting path then this is stripped from the returned value.</returns>
public static string Convert(string fileName, NameExists getFileNameExists)
{
if (fileName == null)
{
return(String.Empty);
}
// Remove invalid characters.
string fileNameWithoutExtension = Path.GetFileNameWithoutExtension(fileName);
string extension = Path.GetExtension(fileName);
StringBuilder shortFileName = new StringBuilder();
int length = 0;
foreach (char ch in fileNameWithoutExtension)
{
if (IsValidShortFileNameChar(ch))
{
shortFileName.Append(ch);
++length;
}
}
// Get truncated extension.
if (extension.Length > MaximumFileNameExtensionLength)
{
extension = extension.Substring(0, MaximumFileNameExtensionLength);
}
// Truncate filename without extension if it is too long.
if (length > MaximumFileNameWithoutExtensionLength)
{
shortFileName.Remove(FileNameWithoutExtensionTruncatedLength, length - FileNameWithoutExtensionTruncatedLength);
return(GetTruncatedFileName(shortFileName.ToString(), extension, getFileNameExists));
}
// Add extension.
shortFileName.Append(extension);
return(shortFileName.ToString().ToUpperInvariant());
}
/// <summary>
/// Truncates the filename start and adds "_N" where N produces a filename that
/// does not exist.
/// </summary>
static string GetTruncatedFileName(string fileNameStart, string extension, NameExists getFileNameExists)
{
return GetUniqueName(fileNameStart.ToUpperInvariant(), "_", extension.ToUpperInvariant(), getFileNameExists);
}
/// <summary>
/// Gets the unique name string by adding a digit until a unique name is
/// produced. The name string itself will be truncated as the number
/// increases in size to make sure the total length of the string is
/// always equal to start.Length + numberPrefix.Length + 1 + end.Length.
/// </summary>
/// <param name="start">The string to be used at the start of the </param>
/// <param name="numberPrefix">The string to be prefixed to the number.</param>
/// <param name="end">The string to be added after the number.</param>
/// <param name="getNameExists">Method called to check that the
/// name does not already exist.</param>
public static string GetUniqueName(string start, string numberPrefix, string end, NameExists getNameExists)
{
int count = 0;
string truncatedName;
int divisor = 10;
do {
++count;
int removeCharCount = count / divisor;
if (removeCharCount > 0) {
start = start.Substring(0, start.Length - 1);
divisor *= divisor;
}
truncatedName = String.Concat(start, numberPrefix, count.ToString(), end);
} while (getNameExists(truncatedName));
return truncatedName;
}
/// <summary>
/// Gets the unique name string by adding a digit until a unique name is
/// produced. The name string itself will be truncated as the number
/// increases in size to make sure the total length of the string is
/// always equal to start.Length + 1.
/// </summary>
/// <param name="start">The string to be used at the start of the </param>
/// <param name="getNameExists">Method called to check that the
/// name does not already exist.</param>
public static string GetUniqueName(string start, NameExists getNameExists)
{
return GetUniqueName(start, String.Empty, String.Empty, getNameExists);
}
/// <summary>
/// Truncates the filename start and adds "_N" where N produces a filename that
/// does not exist.
/// </summary>
static string GetTruncatedFileName(string fileNameStart, string extension, NameExists getFileNameExists)
{
return(GetUniqueName(fileNameStart.ToUpperInvariant(), "_", extension.ToUpperInvariant(), getFileNameExists));
}
/// <summary>
/// Gets the unique name string by adding a digit until a unique name is
/// produced. The name string itself will be truncated as the number
/// increases in size to make sure the total length of the string is
/// always equal to start.Length + numberPrefix.Length + 1 + end.Length.
/// </summary>
/// <param name="start">The string to be used at the start of the </param>
/// <param name="numberPrefix">The string to be prefixed to the number.</param>
/// <param name="end">The string to be added after the number.</param>
/// <param name="getNameExists">Method called to check that the
/// name does not already exist.</param>
public static string GetUniqueName(string start, string numberPrefix, string end, NameExists getNameExists)
{
int count = 0;
string truncatedName;
int divisor = 10;
do
{
++count;
int removeCharCount = count / divisor;
if (removeCharCount > 0)
{
start = start.Substring(0, start.Length - 1);
divisor *= divisor;
}
truncatedName = String.Concat(start, numberPrefix, count.ToString(), end);
} while (getNameExists(truncatedName));
return(truncatedName);
}
/// <summary>
/// Gets the unique name string by adding a digit until a unique name is
/// produced. The name string itself will be truncated as the number
/// increases in size to make sure the total length of the string is
/// always equal to start.Length + 1.
/// </summary>
/// <param name="start">The string to be used at the start of the </param>
/// <param name="getNameExists">Method called to check that the
/// name does not already exist.</param>
public static string GetUniqueName(string start, NameExists getNameExists)
{
return(GetUniqueName(start, String.Empty, String.Empty, getNameExists));
}
