/// <summary>
/// Formats PascalCase (upper CamelCase) and (lower) camelCase words to a friendly format separated by the given delimiter (space by default).
/// </summary>
/// <param name="input">CamelCase input to format</param>
/// <param name="delimiter">Delimiter to use for formatting (space by default)</param>
/// <param name="capitalizeFirstCharacter">Capitalize the first character for (lower) camelCase words (false by default)</param>
public static string FormatCamelCase(string input, string delimiter = " ", CamelCaseOptions camelCaseOptions = CamelCaseOptions.None)
{
if (String.IsNullOrEmpty(delimiter))
{
throw new ArgumentException("Delimiter can't be null or empty", "delimiter");
}
string result;
if (camelCaseOptions.HasFlag(CamelCaseOptions.CapitalizeFirstCharacter) || camelCaseOptions.HasFlag(CamelCaseOptions.CapitalizeFirstCharacterInvariantCulture))
{
result = _formatCamelCaseCapitalizeRegex.Replace(input, m => EvaluateCamelCaseMatchWithCapitalization(m, delimiter, camelCaseOptions));
}
else
{
var replacement = delimiter + "$1";
result = _formatCamelCaseRegex.Replace(input, replacement);
}
return result;
}
/// <summary>
/// Formats PascalCase (upper CamelCase) and (lower) camelCase words to a friendly format separated by the given delimiter (space by default).
/// </summary>
/// <param name="input">CamelCase input to format</param>
/// <param name="delimiter">Delimiter to use for formatting (space by default)</param>
/// <param name="capitalizeFirstCharacter">Capitalize the first character for (lower) camelCase words (false by default)</param>
public static string FormatCamelCase(string input, string delimiter = " ", CamelCaseOptions camelCaseOptions = CamelCaseOptions.None)
{
if (String.IsNullOrEmpty(delimiter))
{
throw new ArgumentException("Delimiter can't be null or empty", "delimiter");
}
string result;
if (camelCaseOptions.HasFlag(CamelCaseOptions.CapitalizeFirstCharacter) || camelCaseOptions.HasFlag(CamelCaseOptions.CapitalizeFirstCharacterInvariantCulture))
{
result = _formatCamelCaseCapitalizeRegex.Replace(input, m => EvaluateCamelCaseMatchWithCapitalization(m, delimiter, camelCaseOptions));
}
else
{
var replacement = delimiter + "$1";
result = _formatCamelCaseRegex.Replace(input, replacement);
}
return(result);
}
private static string EvaluateCamelCaseMatchWithCapitalization(Match m, string delimiter, CamelCaseOptions options)
{
string result;
if (m.Groups["LowerCaseChar"].Value != String.Empty)
{
if (options.HasFlag(CamelCaseOptions.CapitalizeFirstCharacterInvariantCulture))
{
result = m.Groups["LowerCaseChar"].Value.ToUpperInvariant();
}
else
{
result = m.Groups["LowerCaseChar"].Value.ToUpper();
}
}
else
{
result = delimiter + m.Groups[1].Value;
}
return(result);
}
public static string ToLowerCamelCase(this string name, CamelCaseOptions options = default(CamelCaseOptions))
{
Debug.Assert(name != null);
// `n` is the length of `name`.
var n = name.Length;
if (n == 1)
{
return(name.ToLowerInvariant());
}
// `l` is the index of the first lower-case char; or `n` if there is none.
int l;
for (l = 0; l < n && char.IsUpper(name[l]); ++l)
{
;
}
// `i` will be the index of the first character of the resulting name:
int i = 0;
if (l == 0)
{
// `name` already begins with a lower-case char; no need to do anything:
return(name);
}
else if (l == n)
{
// `name` does not contain any lower-case chars:
if ((options & CamelCaseOptions.InterfaceName) != 0 && name[0] == 'I')
{
// possibly an interface name; skip the initial 'I':
++i;
}
else
{
// no interface name; lower-case it as a whole:
return(name.ToLowerInvariant());
}
}
else if (1 < l)
{
// `name` begins with several upper-case chars
if ((options & CamelCaseOptions.InterfaceName) != 0 && name[0] == 'I')
{
// possibly an interface name; skip the initial 'I':
++i;
}
if (i + 1 < l)
{
// if more than one upper-case char (after an optional 'I'), lower-case all but the last:
--l;
}
}
// lower-case the first `l` chars, and append the remaining chars unmodified:
var result = new StringBuilder(n);
for (; i < l; ++i)
{
result.Append(char.ToLowerInvariant(name[i]));
}
result.Append(name, l, n - l);
return(result.ToString());
}
private static string EvaluateCamelCaseMatchWithCapitalization(Match m, string delimiter, CamelCaseOptions options)
{
string result;
if (m.Groups["LowerCaseChar"].Value != String.Empty)
{
if (options.HasFlag(CamelCaseOptions.CapitalizeFirstCharacterInvariantCulture))
{
result = m.Groups["LowerCaseChar"].Value.ToUpperInvariant();
}
else
{
result = m.Groups["LowerCaseChar"].Value.ToUpper();
}
}
else
{
result = delimiter + m.Groups[1].Value;
}
return result;
}