/// <summary>
/// Returns an instance of the <paramref name="type"/>.
/// </summary>
/// <typeparam name="TParam1">The type of the first parameter to pass to the constructor.</typeparam>
/// <typeparam name="TParam2">The type of the second parameter to pass to the constructor.</typeparam>
/// <typeparam name="TParam3">The type of the third parameter to pass to the constructor.</typeparam>
/// <param name="type">The type to be created.</param>
/// <param name="param1">The first parameter to pass to the constructor.</param>
/// <param name="param2">The first parameter to pass to the constructor.</param>
/// <param name="param3">The first parameter to pass to the constructor.</param>
/// <returns>An execution result with an instance of the <paramref name="type"/> if OK,
/// otherwise an empty result with exception.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="type"/> is null.</exception>
/// <exception cref="ArgumentNullException">The <paramref name="param1"/> is null.</exception>
/// <exception cref="ArgumentNullException">The <paramref name="param2"/> is null.</exception>
/// <exception cref="ArgumentNullException">The <paramref name="param3"/> is null.</exception>
public static Optional <object> CreateInstance <TParam1, TParam2, TParam3>(
this Type type,
TParam1 param1,
TParam2 param2,
TParam3 param3)
where TParam1 : notnull
where TParam2 : notnull
where TParam3 : notnull
{
if (type == null)
{
throw new ArgumentNullException(nameof(type));
}
try
{
var lambdaConstructor = GetLambdaConstructor <Func <TParam1, TParam2, TParam3, object> >(
type,
new[] { typeof(TParam1), typeof(TParam2), typeof(TParam3) });
return(lambdaConstructor.Invoke(param1, param2, param3));
}
catch (Exception exception) when(exception is ArgumentException)
{
return(OptionalBuilder.Exception <object>(exception));
}
}
/// <summary>
/// Converts string date to <see cref="DateTime"/> type.
/// If error, returns an exception optional.
/// </summary>
/// <param name="source">A string containing a date and time to convert.</param>
/// <param name="provider">An object that supplies culture-specific format information about string.</param>
/// <param name="styles"> A bitwise combination of enumeration values that indicates the permitted format
/// of string. A typical value to specify is System.Globalization.DateTimeStyles.None.</param>
/// <param name="formats">An array of allowable formats of strings.</param>
/// <returns>An optional instance.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="source"/> is null.</exception>
/// <exception cref="ArgumentNullException">The <paramref name="provider"/> is null.</exception>
public static Optional <DateTime> ToDateTime(
this string source,
IFormatProvider provider,
DateTimeStyles styles,
params string[] formats)
{
if (source is null)
{
throw new ArgumentNullException(nameof(source));
}
if (provider is null)
{
throw new ArgumentNullException(nameof(provider));
}
try
{
if (DateTime.TryParseExact(source, formats, provider, styles, out var dateTime))
{
return(dateTime);
}
return(OptionalBuilder.Empty <DateTime>());
}
catch (Exception exception) when(exception is ArgumentException)
{
return(OptionalBuilder.Exception <DateTime>(exception));
}
}
/// <summary>
/// Invokes the specified member, using the specified binding constraints and matching
/// the specified argument list.
/// </summary>
/// <param name="type"></param>
/// <param name="memberName">The string containing the name of the constructor, method, property, or field
/// member to invoke. /// -or- /// An empty string ("") to invoke the default
/// member. /// -or- /// For IDispatch members, a string representing the DispID,
/// for example "[DispID=3]".</param>
/// <param name="invokeAttr">A bitmask comprised of one or more System.Reflection.BindingFlags that specify
/// how the search is conducted. The access can be one of the BindingFlags such as
/// Public, NonPublic, Private, InvokeMethod, GetField, and so on. The type of lookup
/// need not be specified. If the type of lookup is omitted, BindingFlags.Public
/// | BindingFlags.Instance | BindingFlags.Static are used.</param>
/// <param name="binder">An object that defines a set of properties and enables binding, which can involve
/// selection of an overloaded method, coercion of argument types, and invocation
/// of a member through reflection. /// -or- /// A null reference (Nothing in Visual
/// Basic), to use the System.Type.DefaultBinder. Note that explicitly defining a
/// System.Reflection.Binder object may be required for successfully invoking method
/// overloads with variable arguments.</param>
/// <param name="target">The object on which to invoke the specified member.</param>
/// <param name="args">An array containing the arguments to pass to the member to invoke.</param>
/// <returns>An object representing the return value of the invoked member
/// or an empty result with handled exception.</returns>
public static Optional <object> TypeInvokeMember(
this Type type,
string memberName,
BindingFlags invokeAttr,
Binder binder,
object target,
object[] args)
{
if (type == null)
{
throw new ArgumentNullException(nameof(type));
}
if (string.IsNullOrWhiteSpace(memberName))
{
throw new ArgumentNullException(nameof(memberName));
}
try
{
return(type.InvokeMember(memberName, invokeAttr, binder, target, args, CultureInfo.InvariantCulture));
}
catch (Exception exception) when(exception is ArgumentNullException ||
exception is ArgumentException ||
exception is MethodAccessException ||
exception is MissingFieldException ||
exception is MissingMethodException ||
exception is TargetException ||
exception is AmbiguousMatchException ||
exception is InvalidOperationException)
{
return(OptionalBuilder.Exception <object>(exception));
}
}
/// <summary>
/// Converts the current enumeration value to the target one.
/// </summary>
/// <typeparam name="TEnum">Type of target value.</typeparam>
/// <param name="source">The current enumeration value.</param>
/// <returns>An new enumeration of <typeparamref name="TEnum"/> type.</returns>
/// <exception cref="InvalidOperationException">The conversion failed. See inner exception.</exception>
public static Optional <TEnum> ConvertTo <TEnum>(this string source)
where TEnum : struct, Enum
{
try
{
return((TEnum)Enum.Parse(typeof(TEnum), source));
}
catch (OverflowException exception)
{
return(OptionalBuilder.Exception <TEnum>(exception));
}
}
/// <summary>
/// Converts a string to a value type.
/// </summary>
/// <typeparam name="T">Type source.</typeparam>
/// <param name="value">The string value.</param>
/// <returns>The string value converted to the specified value type.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="value"/> is null or empty.</exception>
public static Optional <T> ToValueType <T>(this string value)
where T : struct, IComparable, IFormattable, IConvertible, IComparable <T>, IEquatable <T>
{
try
{
return((T)Convert.ChangeType(value, typeof(T), CultureInfo.CurrentCulture));
}
catch (Exception exception) when(exception is InvalidCastException ||
exception is FormatException ||
exception is OverflowException)
{
return(OptionalBuilder.Exception <T>(exception));
}
}
/// <summary>
/// Returns an instance of the <paramref name="type"/>.
/// </summary>
/// <param name="type">The type to be created.</param>
/// <returns>An execution result with an instance of the <paramref name="type"/> if OK,
/// otherwise an empty result with exception.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="type"/> is null.</exception>
public static Optional <object> CreateInstance(this Type type)
{
if (type is null)
{
throw new ArgumentNullException(nameof(type));
}
try
{
var lambdaConstructor = GetLambdaConstructor <Func <object> >(type, Array.Empty <Type>());
return(lambdaConstructor.Invoke());
}
catch (Exception exception) when(exception is ArgumentException)
{
return(OptionalBuilder.Exception <object>(exception));
}
}
/// <summary>
/// Substitutes the elements of an array of types for the type parameters of the
/// current generic type definition and returns a System.Type object representing
/// the resulting constructed type. If error, return an optional with exception.
/// </summary>
/// <param name="type">The type to act on.</param>
/// <param name="typeArguments">An array of types to be substituted for the type parameters of the current generic
/// type.</param>
/// <exception cref="ArgumentNullException">The <paramref name="type"/> is null.</exception>
public static Optional <Type> MakeGenericTypeSafe(this Type type, params Type[] typeArguments)
{
if (type == null)
{
throw new ArgumentNullException(nameof(type));
}
try
{
return(type.MakeGenericType(typeArguments));
}
catch (Exception exception) when(exception is InvalidOperationException ||
exception is ArgumentException ||
exception is NotSupportedException)
{
return(OptionalBuilder.Exception <Type>(exception));
}
}
/// <summary>
/// Returns the attribute of the <typeparamref name="TAttribute"/> type from the type.
/// </summary>
/// <typeparam name="TAttribute">Type of attribute.</typeparam>
/// <param name="source">enumeration instance to act on.</param>
/// <param name="inherit"><see langword="true"/> to inspect the ancestors of element;
/// otherwise, <see langword="false"/>.</param>
/// <returns>The description string. If not found, returns the enumeration as string.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="source"/> is null.</exception>
public static Optional <TAttribute> GetAttribute <TAttribute>(this PropertyInfo source, bool inherit = true)
where TAttribute : Attribute
{
if (source is null)
{
throw new ArgumentNullException(nameof(source));
}
try
{
return(source.GetType().GetTypeInfo().GetCustomAttribute <TAttribute>(inherit));
}
catch (Exception exception) when(exception is NotSupportedException ||
exception is AmbiguousMatchException ||
exception is TypeLoadException)
{
return(OptionalBuilder.Exception <TAttribute>(exception));
}
}
/// <summary>
/// Returns a loaded assembly from its name.
/// </summary>
/// <param name="assemblyName">The assembly name.</param>
/// <returns>If found, returns a loaded assembly otherwise an empty result.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="assemblyName"/> is null.</exception>
public static Optional <Assembly> AssemblyLoadedFromString(this string assemblyName)
{
if (assemblyName is null)
{
throw new ArgumentNullException(nameof(assemblyName));
}
try
{
return(Assembly.Load(assemblyName));
}
catch (Exception exception) when(exception is ArgumentException ||
exception is FileNotFoundException ||
exception is FileLoadException ||
exception is BadImageFormatException)
{
return(OptionalBuilder.Exception <Assembly>(exception));
}
}
/// <summary>
/// Generates a string of the specified length that contains random characters from the lookup characters.
/// <para>The implementation uses the <see cref="RNGCryptoServiceProvider"/>.</para>
/// </summary>
/// <remarks>
/// Inspiration from https://stackoverflow.com/questions/32932679/using-rngcryptoserviceprovider-to-generate-random-string
/// </remarks>
/// <param name="lookupChar">The string to be used to pick characters from.</param>
/// <param name="length">The length of the expected string value.</param>
/// <returns>A new string of the specified length with random characters.</returns>
/// <exception cref="ArgumentOutOfRangeException">The <paramref name="length"/> is lower or equal to zero.</exception>
/// <exception cref="ArgumentNullException">The <paramref name="lookupChar"/> is null.</exception>
public static Optional <string> GenerateString(this string lookupChar, int length)
{
if (length <= 0)
{
throw new ArgumentOutOfRangeException(nameof(length));
}
if (string.IsNullOrWhiteSpace(lookupChar))
{
throw new ArgumentNullException(nameof(lookupChar));
}
try
{
var stringResult = new StringBuilder(length);
using (var random = new RNGCryptoServiceProvider())
{
var count = (int)Math.Ceiling(Math.Log(lookupChar.Length, 2) / 8.0);
Diagnostics.Debug.Assert(count <= sizeof(uint));
var offset = BitConverter.IsLittleEndian ? 0 : sizeof(uint) - count;
var max = (int)(Math.Pow(2, count * 8) / lookupChar.Length) * lookupChar.Length;
var uintBuffer = new byte[sizeof(uint)];
while (stringResult.Length < length)
{
random.GetBytes(uintBuffer, offset, count);
var number = BitConverter.ToUInt32(uintBuffer, 0);
if (number < max)
{
stringResult.Append(lookupChar[(int)(number % lookupChar.Length)]);
}
}
}
return(stringResult.ToString());
}
catch (Exception exception) when(exception is ArgumentOutOfRangeException ||
exception is ArgumentException)
{
return(OptionalBuilder.Exception <string>(exception));
}
}
/// <summary>
/// Returns type from its string name.
/// </summary>
/// <param name="typeName">The name of the type to find.</param>
/// <returns>if found, returns the type otherwise an empty result.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="typeName"/> is null.</exception>
public static Optional <Type> TypeFromString(this string typeName)
{
if (string.IsNullOrWhiteSpace(typeName))
{
throw new ArgumentNullException(nameof(typeName));
}
try
{
return(Type.GetType(typeName, true, true));
}
catch (Exception exception) when(exception is TargetInvocationException ||
exception is TypeLoadException ||
exception is ArgumentException ||
exception is FileNotFoundException ||
exception is FileLoadException ||
exception is BadImageFormatException)
{
return(OptionalBuilder.Exception <Type>(exception));
}
}
/// <summary>
/// Converts the value of the current System.DateTime object to its equivalent string
/// representation using the specified format and culture-specific format information.
/// If error, returns an exception
/// </summary>
/// <param name="dateTime">The date time to be converted.</param>
/// <param name="format">A standard or custom date and time format string.</param>
/// <param name="provider">An object that supplies culture-specific formatting information.</param>
/// <returns>An optional string representation of value of the current System.DateTime object as specified
/// by format and provider.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="format"/> is null.</exception>
/// <exception cref="ArgumentNullException">The <paramref name="provider"/> is null.</exception>
public static Optional <string> DateTimeToString(this DateTime dateTime, string format, IFormatProvider provider)
{
if (format is null)
{
throw new ArgumentNullException(nameof(format));
}
if (provider is null)
{
throw new ArgumentNullException(nameof(provider));
}
try
{
return(dateTime.ToString(format, provider));
}
catch (Exception exception) when(exception is FormatException ||
exception is ArgumentOutOfRangeException)
{
return(OptionalBuilder.Exception <string>(exception));
}
}
/// <summary>
/// Returns an encrypted string from the value using the specified key.
/// <para>The implementation uses the <see cref="SHA512Managed"/>.</para>
/// </summary>
/// <param name="source">The value to be encrypted.</param>
/// <param name="key">The key value to be used for encryption.</param>
/// <returns>An encrypted object that contains the encrypted value and its key.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="source"/> is null.</exception>
/// <exception cref="ArgumentNullException">The <paramref name="key"/> is null.</exception>
public static Optional <string> Encrypt(this string source, string key)
{
if (string.IsNullOrWhiteSpace(source))
{
throw new ArgumentNullException(nameof(source));
}
if (string.IsNullOrWhiteSpace(key))
{
throw new ArgumentNullException(nameof(key));
}
try
{
using var cryptoManaged = new SHA512Managed();
var data = Text.Encoding.UTF8.GetBytes(source);
var hash = cryptoManaged.ComputeHash(data);
return(BitConverter.ToString(hash).Replace("-", string.Empty, StringComparison.OrdinalIgnoreCase));
}
catch (Exception exception) when(exception is Text.EncoderFallbackException || exception is ObjectDisposedException)
{
return(OptionalBuilder.Exception <string>(exception));
}
}
/// <summary>
/// Returns the type, if not found, try to load from the assembly.
/// </summary>
/// <param name="typeName">The name of the type to find.</param>
/// <param name="assemblyName">The assembly to act on.</param>
/// <returns>if found, returns the type otherwise an empty result.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="typeName"/> is null.</exception>
/// <exception cref="ArgumentNullException">The <paramref name="assemblyName"/> is null.</exception>
public static Optional <Type> TypeFromString(this string typeName, string assemblyName)
{
if (string.IsNullOrWhiteSpace(assemblyName))
{
throw new ArgumentNullException(nameof(assemblyName));
}
if (string.IsNullOrWhiteSpace(typeName))
{
throw new ArgumentNullException(nameof(typeName));
}
var resultFromType = TypeFromString(typeName);
if (resultFromType.Any())
{
return(resultFromType);
}
var resultFromAss = AssemblyLoadedFromString(assemblyName);
if (resultFromAss.Any())
{
var resultLoadedType = resultFromAss.Single()
.GetExportedTypes()
.FirstOrEmpty(t => t.FullName.Equals(typeName, StringComparison.InvariantCultureIgnoreCase));
return(resultLoadedType
.Map(value => value));
}
var exception = default(Exception) !;
resultFromAss.WhenException(ex => exception = ex);
return(OptionalBuilder.Exception <Type>(exception));
}
