/// <summary>
/// Returns a random string.
/// </summary>
/// <param name="length">The length of the string.</param>
/// <param name="pool">Characters pool</param>
/// <param name="alpha">Set to True to use only an alphanumeric character.</param>
/// <param name="symbols">Set to true to return only symbols.</param>
/// <param name="casing">Default casing.</param>
/// <exception cref="ArgumentException">Thrown when <c>length</c> is less than 0.</exception>
/// <returns>Returns a random string.</returns>
public string NextString(int length = 10, string pool = null, bool alpha = false, bool symbols = false,
CasingRules casing = CasingRules.MixedCase)
{
if (length < 0)
{
throw new ArgumentException("Length cannot be less than zero.", nameof(length));
}
return(string.Join("",
NextList <char>(new Func <string, bool, bool, CasingRules, char>(NextChar), length, pool, alpha, symbols,
casing)));
}
/// <summary>
/// Returns a random character.
/// </summary>
/// <param name="pool">Characters pool</param>
/// <param name="alpha">Set to True to use only an alphanumeric character.</param>
/// <param name="symbols">Set to true to return only symbols.</param>
/// <param name="casing">Default casing.</param>
/// <returns>Returns a random character.</returns>
public char NextChar(
string pool = null,
bool alpha = false,
bool symbols = false,
CasingRules casing = CasingRules.MixedCase)
{
const string SpecialCharacters = "!@#$%^&*()[]";
string letters, p;
if (alpha && symbols)
{
throw new ArgumentException("Cannot specify both alpha and symbols.");
}
if (casing == CasingRules.LowerCase)
{
letters = CharsLower;
}
else if (casing == CasingRules.UpperCase)
{
letters = CharsUpper;
}
else
{
letters = CharsLower + CharsUpper;
}
if (!string.IsNullOrEmpty(pool))
{
p = pool;
}
else if (alpha)
{
p = letters;
}
else if (symbols)
{
p = SpecialCharacters;
}
else
{
p = letters + Numbers + SpecialCharacters;
}
return(p[this.NextNatural(max: p.Length - 1)]);
}