public void TestToDouble()
{
Assert.Null(DoubleConverter.ToNullableDouble(null));
Assert.True(Math.Abs(123 - DoubleConverter.ToDouble(123)) < 0.001);
Assert.True(Math.Abs(123.456 - DoubleConverter.ToDouble(123.456)) < 0.001);
Assert.True(Math.Abs(123.456 - DoubleConverter.ToDouble("123.456")) < 0.001);
Assert.True(Math.Abs(123 - DoubleConverter.ToDoubleWithDefault(null, 123)) < 0.001);
Assert.True(Math.Abs(0 - DoubleConverter.ToDoubleWithDefault(false, 123)) < 0.001);
Assert.True(Math.Abs(123 - DoubleConverter.ToDoubleWithDefault("ABC", 123)) < 0.001);
}
/// <summary>
/// Converts value into an object type specified by Type Code
/// or returns default value when conversion is not possible.
/// </summary>
/// <typeparam name="T">the Class type for the data type into which 'value' is to be converted.</typeparam>
/// <param name="value">the value to convert.</param>
/// <param name="defaultValue">the default value to return if conversion is not possible
/// (returns null).</param>
/// <returns>object value of type corresponding to TypeCode, or default value when
/// conversion is not supported</returns>
public static T ToTypeWithDefault <T>(object value, T defaultValue)
{
if (value == null)
{
return(defaultValue);
}
if (value is T)
{
return((T)value);
}
var typeInfo = typeof(T).GetTypeInfo();
if (typeInfo.IsEnum)
{
value = EnumConverter.ToEnumWithDefault <T>(value, defaultValue);
}
else if (typeInfo.IsAssignableFrom(typeof(decimal)))
{
value = DecimalConverter.ToNullableDecimal(value);
}
else if (typeInfo.IsAssignableFrom(typeof(string)))
{
value = StringConverter.ToNullableString(value);
}
else if (typeInfo.IsAssignableFrom(typeof(long)))
{
value = LongConverter.ToNullableLong(value);
}
else if (typeInfo.IsAssignableFrom(typeof(int)))
{
value = IntegerConverter.ToNullableInteger(value);
}
else if (typeInfo.IsAssignableFrom(typeof(double)))
{
value = DoubleConverter.ToNullableDouble(value);
}
else if (typeInfo.IsAssignableFrom(typeof(float)))
{
value = FloatConverter.ToNullableFloat(value);
}
else if (typeInfo.IsAssignableFrom(typeof(bool)))
{
value = BooleanConverter.ToNullableBoolean(value);
}
else if (typeInfo.IsAssignableFrom(typeof(DateTime)))
{
value = DateTimeConverter.ToNullableDateTime(value);
}
else if (typeInfo.IsAssignableFrom(typeof(TimeSpan)))
{
value = TimeSpanConverter.ToNullableTimeSpan(value);
}
if (value == null)
{
return(defaultValue);
}
try
{
if (typeInfo.IsClass || typeInfo.IsInterface)
{
return(value is T ? (T)value : defaultValue);
}
else
{
return((T)value);
}
}
catch
{
return(defaultValue);
}
}
/// <summary>
/// Converts value into an object type specified by Type Code or returns null
/// when conversion is not possible.
/// </summary>
/// <typeparam name="T">the Class type for the data type.</typeparam>
/// <param name="value">the value to convert.</param>
/// <returns>object value of type corresponding to TypeCode, or null when
/// conversion is not supported.</returns>
/// See <see cref="TypeConverter.ToTypeCode(Type)"/>
public static T?ToNullableType <T>(object value) where T : struct
{
if (value == null)
{
return(null);
}
if (value is T)
{
return((T)value);
}
var typeInfo = typeof(T).GetTypeInfo();
if (typeInfo.IsEnum)
{
value = EnumConverter.ToNullableEnum <T>(value);
}
else if (typeInfo.IsAssignableFrom(typeof(decimal)))
{
value = DecimalConverter.ToNullableDecimal(value);
}
else if (typeInfo.IsAssignableFrom(typeof(string)))
{
value = StringConverter.ToNullableString(value);
}
else if (typeInfo.IsAssignableFrom(typeof(long)))
{
value = LongConverter.ToNullableLong(value);
}
else if (typeInfo.IsAssignableFrom(typeof(int)))
{
value = IntegerConverter.ToNullableInteger(value);
}
else if (typeInfo.IsAssignableFrom(typeof(double)))
{
value = DoubleConverter.ToNullableDouble(value);
}
else if (typeInfo.IsAssignableFrom(typeof(float)))
{
value = FloatConverter.ToNullableFloat(value);
}
else if (typeInfo.IsAssignableFrom(typeof(DateTime)))
{
value = DateTimeConverter.ToNullableDateTime(value);
}
else if (typeInfo.IsAssignableFrom(typeof(TimeSpan)))
{
value = TimeSpanConverter.ToNullableTimeSpan(value);
}
if (value == null)
{
return(null);
}
try
{
return((T)value);
}
catch
{
return(null);
}
}