ConvertUtils.cs | searchcode

/monotouch/Newtonsoft.Json/Utilities/ConvertUtils.cs

https://github.com/Sfyler/c-sharp
C# | 515 lines | 310 code | 71 blank | 134 comment | 115 complexity | 83e565f1239b5ab433b8df054bf886fc MD5 | raw file
Possible License(s): BSD-3-Clause

#region License

// Copyright (c) 2007 James Newton-King

//

// Permission is hereby granted, free of charge, to any person

// obtaining a copy of this software and associated documentation

// files (the "Software"), to deal in the Software without

// restriction, including without limitation the rights to use,

// copy, modify, merge, publish, distribute, sublicense, and/or sell

// copies of the Software, and to permit persons to whom the

// Software is furnished to do so, subject to the following

// conditions:

//

// The above copyright notice and this permission notice shall be

// included in all copies or substantial portions of the Software.

//

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

// OTHER DEALINGS IN THE SOFTWARE.

#endregion



using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Globalization;

using System.ComponentModel;

using Newtonsoft.Json.Serialization;

using System.Reflection;



#if !(SILVERLIGHT || MONODROID || MONOTOUCH)

using System.Data.SqlTypes;

#endif



namespace Newtonsoft.Json.Utilities

{

  internal static class ConvertUtils

  {

    internal struct TypeConvertKey : IEquatable<TypeConvertKey>

    {

      private readonly Type _initialType;

      private readonly Type _targetType;



      public Type InitialType

      {

        get { return _initialType; }

      }



      public Type TargetType

      {

        get { return _targetType; }

      }



      public TypeConvertKey(Type initialType, Type targetType)

      {

        _initialType = initialType;

        _targetType = targetType;

      }



      public override int GetHashCode()

      {

        return _initialType.GetHashCode() ^ _targetType.GetHashCode();

      }



      public override bool Equals(object obj)

      {

        if (!(obj is TypeConvertKey))

          return false;



        return Equals((TypeConvertKey)obj);

      }



      public bool Equals(TypeConvertKey other)

      {

        return (_initialType == other._initialType && _targetType == other._targetType);

      }

    }



    private static readonly ThreadSafeStore<TypeConvertKey, Func<object, object>> CastConverters =

      new ThreadSafeStore<TypeConvertKey, Func<object, object>>(CreateCastConverter);



    private static Func<object, object> CreateCastConverter(TypeConvertKey t)

    {

      MethodInfo castMethodInfo = t.TargetType.GetMethod("op_Implicit", new[] { t.InitialType });

      if (castMethodInfo == null)

        castMethodInfo = t.TargetType.GetMethod("op_Explicit", new[] { t.InitialType });



      if (castMethodInfo == null)

        return null;



      MethodCall<object, object> call = JsonTypeReflector.ReflectionDelegateFactory.CreateMethodCall<object>(castMethodInfo);



      return o => call(null, o);

    }



    public static bool CanConvertType(Type initialType, Type targetType, bool allowTypeNameToString)

    {

      ValidationUtils.ArgumentNotNull(initialType, "initialType");

      ValidationUtils.ArgumentNotNull(targetType, "targetType");



      if (ReflectionUtils.IsNullableType(targetType))

        targetType = Nullable.GetUnderlyingType(targetType);



      if (targetType == initialType)

        return true;



      if (typeof(IConvertible).IsAssignableFrom(initialType) && typeof(IConvertible).IsAssignableFrom(targetType))

      {

        return true;

      }



#if !PocketPC && !NET20

      if (initialType == typeof(DateTime) && targetType == typeof(DateTimeOffset))

        return true;

#endif



      if (initialType == typeof(Guid) && (targetType == typeof(Guid) || targetType == typeof(string)))

        return true;



      if (initialType == typeof(Type) && targetType == typeof(string))

        return true;



#if !PocketPC

      // see if source or target types have a TypeConverter that converts between the two

      TypeConverter toConverter = GetConverter(initialType);



      if (toConverter != null && !IsComponentConverter(toConverter) && toConverter.CanConvertTo(targetType))

      {

        if (allowTypeNameToString || toConverter.GetType() != typeof(TypeConverter))

          return true;

      }



      TypeConverter fromConverter = GetConverter(targetType);



      if (fromConverter != null && !IsComponentConverter(fromConverter) && fromConverter.CanConvertFrom(initialType))

        return true;

#endif



      // handle DBNull and INullable

      if (initialType == typeof(DBNull))

      {

        if (ReflectionUtils.IsNullable(targetType))

          return true;

      }



      return false;

    }



    private static bool IsComponentConverter(TypeConverter converter)

    {

#if !SILVERLIGHT && !PocketPC

      return (converter is ComponentConverter);

#else

      return false;

#endif

    }



    #region Convert

    /// <summary>

    /// Converts the value to the specified type.

    /// </summary>

    /// <typeparam name="T">The type to convert the value to.</typeparam>

    /// <param name="initialValue">The value to convert.</param>

    /// <returns>The converted type.</returns>

    public static T Convert<T>(object initialValue)

    {

      return Convert<T>(initialValue, CultureInfo.CurrentCulture);

    }



    /// <summary>

    /// Converts the value to the specified type.

    /// </summary>

    /// <typeparam name="T">The type to convert the value to.</typeparam>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="culture">The culture to use when converting.</param>

    /// <returns>The converted type.</returns>

    public static T Convert<T>(object initialValue, CultureInfo culture)

    {

      return (T)Convert(initialValue, culture, typeof(T));

    }



    /// <summary>

    /// Converts the value to the specified type.

    /// </summary>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="culture">The culture to use when converting.</param>

    /// <param name="targetType">The type to convert the value to.</param>

    /// <returns>The converted type.</returns>

    public static object Convert(object initialValue, CultureInfo culture, Type targetType)

    {

      if (initialValue == null)

        throw new ArgumentNullException("initialValue");



      if (ReflectionUtils.IsNullableType(targetType))

        targetType = Nullable.GetUnderlyingType(targetType);



      Type initialType = initialValue.GetType();



      if (targetType == initialType)

        return initialValue;



      if (initialValue is string && typeof(Type).IsAssignableFrom(targetType))

        return Type.GetType((string) initialValue, true);



      if (targetType.IsInterface || targetType.IsGenericTypeDefinition || targetType.IsAbstract)

        throw new ArgumentException("Target type {0} is not a value type or a non-abstract class.".FormatWith(CultureInfo.InvariantCulture, targetType), "targetType");



      // use Convert.ChangeType if both types are IConvertible

      if (initialValue is IConvertible && typeof(IConvertible).IsAssignableFrom(targetType))

      {

        if (targetType.IsEnum)

        {

          if (initialValue is string)

            return Enum.Parse(targetType, initialValue.ToString(), true);

          else if (IsInteger(initialValue))

            return Enum.ToObject(targetType, initialValue);

        }

        

        return System.Convert.ChangeType(initialValue, targetType, culture);

      }



#if !PocketPC && !NET20

      if (initialValue is DateTime && targetType == typeof(DateTimeOffset))

        return new DateTimeOffset((DateTime)initialValue);

#endif



      if (initialValue is string)

      {

        if (targetType == typeof (Guid))

          return new Guid((string) initialValue);

        if (targetType == typeof (Uri))

          return new Uri((string) initialValue);

        if (targetType == typeof (TimeSpan))

#if !(NET35 || NET20 || SILVERLIGHT)

          return TimeSpan.Parse((string) initialValue, CultureInfo.InvariantCulture);

#else

          return TimeSpan.Parse((string)initialValue);

#endif

      }



#if !PocketPC

      // see if source or target types have a TypeConverter that converts between the two

      TypeConverter toConverter = GetConverter(initialType);



      if (toConverter != null && toConverter.CanConvertTo(targetType))

      {

#if !SILVERLIGHT

        return toConverter.ConvertTo(null, culture, initialValue, targetType);

#else

        return toConverter.ConvertTo(initialValue, targetType);

#endif

      }



      TypeConverter fromConverter = GetConverter(targetType);



      if (fromConverter != null && fromConverter.CanConvertFrom(initialType))

      {

#if !SILVERLIGHT

        return fromConverter.ConvertFrom(null, culture, initialValue);

#else

        return fromConverter.ConvertFrom(initialValue);

#endif

      }

#endif



      // handle DBNull and INullable

      if (initialValue == DBNull.Value)

      {

        if (ReflectionUtils.IsNullable(targetType))

          return EnsureTypeAssignable(null, initialType, targetType);

        

        throw new Exception("Can not convert null {0} into non-nullable {1}.".FormatWith(CultureInfo.InvariantCulture, initialType, targetType));

      }

#if !(SILVERLIGHT || MONODROID || MONOTOUCH)

      if (initialValue is INullable)

        return EnsureTypeAssignable(ToValue((INullable)initialValue), initialType, targetType);

#endif



      throw new Exception("Can not convert from {0} to {1}.".FormatWith(CultureInfo.InvariantCulture, initialType, targetType));

    }

    #endregion



    #region TryConvert

    /// <summary>

    /// Converts the value to the specified type.

    /// </summary>

    /// <typeparam name="T">The type to convert the value to.</typeparam>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="convertedValue">The converted value if the conversion was successful or the default value of <c>T</c> if it failed.</param>

    /// <returns>

    ///     <c>true</c> if <c>initialValue</c> was converted successfully; otherwise, <c>false</c>.

    /// </returns>

    public static bool TryConvert<T>(object initialValue, out T convertedValue)

    {

      return TryConvert(initialValue, CultureInfo.CurrentCulture, out convertedValue);

    }



    /// <summary>

    /// Converts the value to the specified type.

    /// </summary>

    /// <typeparam name="T">The type to convert the value to.</typeparam>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="culture">The culture to use when converting.</param>

    /// <param name="convertedValue">The converted value if the conversion was successful or the default value of <c>T</c> if it failed.</param>

    /// <returns>

    ///     <c>true</c> if <c>initialValue</c> was converted successfully; otherwise, <c>false</c>.

    /// </returns>

    public static bool TryConvert<T>(object initialValue, CultureInfo culture, out T convertedValue)

    {

      return MiscellaneousUtils.TryAction<T>(delegate

      {

        object tempConvertedValue;

        TryConvert(initialValue, CultureInfo.CurrentCulture, typeof(T), out tempConvertedValue);



        return (T)tempConvertedValue;

      }, out convertedValue);

    }



    /// <summary>

    /// Converts the value to the specified type.

    /// </summary>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="culture">The culture to use when converting.</param>

    /// <param name="targetType">The type to convert the value to.</param>

    /// <param name="convertedValue">The converted value if the conversion was successful or the default value of <c>T</c> if it failed.</param>

    /// <returns>

    ///     <c>true</c> if <c>initialValue</c> was converted successfully; otherwise, <c>false</c>.

    /// </returns>

    public static bool TryConvert(object initialValue, CultureInfo culture, Type targetType, out object convertedValue)

    {

      return MiscellaneousUtils.TryAction<object>(delegate { return Convert(initialValue, culture, targetType); }, out convertedValue);

    }

    #endregion



    #region ConvertOrCast

    /// <summary>

    /// Converts the value to the specified type. If the value is unable to be converted, the

    /// value is checked whether it assignable to the specified type.

    /// </summary>

    /// <typeparam name="T">The type to convert or cast the value to.</typeparam>

    /// <param name="initialValue">The value to convert.</param>

    /// <returns>The converted type. If conversion was unsuccessful, the initial value is returned if assignable to the target type</returns>

    public static T ConvertOrCast<T>(object initialValue)

    {

      return ConvertOrCast<T>(initialValue, CultureInfo.CurrentCulture);

    }



    /// <summary>

    /// Converts the value to the specified type. If the value is unable to be converted, the

    /// value is checked whether it assignable to the specified type.

    /// </summary>

    /// <typeparam name="T">The type to convert or cast the value to.</typeparam>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="culture">The culture to use when converting.</param>

    /// <returns>The converted type. If conversion was unsuccessful, the initial value is returned if assignable to the target type</returns>

    public static T ConvertOrCast<T>(object initialValue, CultureInfo culture)

    {

      return (T)ConvertOrCast(initialValue, culture, typeof(T));

    }



    /// <summary>

    /// Converts the value to the specified type. If the value is unable to be converted, the

    /// value is checked whether it assignable to the specified type.

    /// </summary>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="culture">The culture to use when converting.</param>

    /// <param name="targetType">The type to convert or cast the value to.</param>

    /// <returns>

    /// The converted type. If conversion was unsuccessful, the initial value

    /// is returned if assignable to the target type.

    /// </returns>

    public static object ConvertOrCast(object initialValue, CultureInfo culture, Type targetType)

    {

      object convertedValue;



      if (targetType == typeof(object))

        return initialValue;



      if (initialValue == null && ReflectionUtils.IsNullable(targetType))

        return null;



      if (TryConvert(initialValue, culture, targetType, out convertedValue))

        return convertedValue;



      return EnsureTypeAssignable(initialValue, ReflectionUtils.GetObjectType(initialValue), targetType);

    }

    #endregion



    #region TryConvertOrCast

    /// <summary>

    /// Converts the value to the specified type. If the value is unable to be converted, the

    /// value is checked whether it assignable to the specified type.

    /// </summary>

    /// <typeparam name="T">The type to convert the value to.</typeparam>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="convertedValue">The converted value if the conversion was successful or the default value of <c>T</c> if it failed.</param>

    /// <returns>

    ///     <c>true</c> if <c>initialValue</c> was converted successfully or is assignable; otherwise, <c>false</c>.

    /// </returns>

    public static bool TryConvertOrCast<T>(object initialValue, out T convertedValue)

    {

      return TryConvertOrCast<T>(initialValue, CultureInfo.CurrentCulture, out convertedValue);

    }



    /// <summary>

    /// Converts the value to the specified type. If the value is unable to be converted, the

    /// value is checked whether it assignable to the specified type.

    /// </summary>

    /// <typeparam name="T">The type to convert the value to.</typeparam>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="culture">The culture to use when converting.</param>

    /// <param name="convertedValue">The converted value if the conversion was successful or the default value of <c>T</c> if it failed.</param>

    /// <returns>

    ///     <c>true</c> if <c>initialValue</c> was converted successfully or is assignable; otherwise, <c>false</c>.

    /// </returns>

    public static bool TryConvertOrCast<T>(object initialValue, CultureInfo culture, out T convertedValue)

    {

      return MiscellaneousUtils.TryAction<T>(delegate

      {

        object tempConvertedValue;

        TryConvertOrCast(initialValue, CultureInfo.CurrentCulture, typeof(T), out tempConvertedValue);



        return (T)tempConvertedValue;

      }, out convertedValue);

    }



    /// <summary>

    /// Converts the value to the specified type. If the value is unable to be converted, the

    /// value is checked whether it assignable to the specified type.

    /// </summary>

    /// <param name="initialValue">The value to convert.</param>

    /// <param name="culture">The culture to use when converting.</param>

    /// <param name="targetType">The type to convert the value to.</param>

    /// <param name="convertedValue">The converted value if the conversion was successful or the default value of <c>T</c> if it failed.</param>

    /// <returns>

    ///     <c>true</c> if <c>initialValue</c> was converted successfully or is assignable; otherwise, <c>false</c>.

    /// </returns>

    public static bool TryConvertOrCast(object initialValue, CultureInfo culture, Type targetType, out object convertedValue)

    {

      return MiscellaneousUtils.TryAction<object>(delegate { return ConvertOrCast(initialValue, culture, targetType); }, out convertedValue);

    }

    #endregion



    private static object EnsureTypeAssignable(object value, Type initialType, Type targetType)

    {

      Type valueType = (value != null) ? value.GetType() : null;



      if (value != null)

      {

        if (targetType.IsAssignableFrom(valueType))

          return value;



        Func<object, object> castConverter = CastConverters.Get(new TypeConvertKey(valueType, targetType));

        if (castConverter != null)

          return castConverter(value);

      }

      else

      {

        if (ReflectionUtils.IsNullable(targetType))

          return null;

      }



      throw new Exception("Could not cast or convert from {0} to {1}.".FormatWith(CultureInfo.InvariantCulture, (initialType != null) ? initialType.ToString() : "{null}", targetType));

    }



#if !(SILVERLIGHT || MONODROID || MONOTOUCH)

    public static object ToValue(INullable nullableValue)

    {

      if (nullableValue == null)

        return null;

      else if (nullableValue is SqlInt32)

        return ToValue((SqlInt32)nullableValue);

      else if (nullableValue is SqlInt64)

        return ToValue((SqlInt64)nullableValue);

      else if (nullableValue is SqlBoolean)

        return ToValue((SqlBoolean)nullableValue);

      else if (nullableValue is SqlString)

        return ToValue((SqlString)nullableValue);

      else if (nullableValue is SqlDateTime)

        return ToValue((SqlDateTime)nullableValue);



      throw new Exception("Unsupported INullable type: {0}".FormatWith(CultureInfo.InvariantCulture, nullableValue.GetType()));

    }

#endif



#if !PocketPC

    internal static TypeConverter GetConverter(Type t)

    {

      return JsonTypeReflector.GetTypeConverter(t);

    }

#endif



    public static bool IsInteger(object value)

    {

      switch (System.Convert.GetTypeCode(value))

      {

        case TypeCode.SByte:

        case TypeCode.Byte:

        case TypeCode.Int16:

        case TypeCode.UInt16:

        case TypeCode.Int32:

        case TypeCode.UInt32:

        case TypeCode.Int64:

        case TypeCode.UInt64:

          return true;

        default:

          return false;

      }

    }

  }

}