/// <summary>
/// Gets the single <see cref="SubstituteType"/> from the <see cref="IArgumentNullExceptionFixture.Mappings"/>.
/// </summary>
/// <param name="fixture">The fixture.</param>
/// <returns>The single <see cref="SubstituteType"/> from the
/// <see cref="IArgumentNullExceptionFixture.Mappings"/>.</returns>
/// <exception cref="ArgumentNullException">The <paramref name="fixture"/> parameter is
/// <see langword="null"/>.</exception>
/// <exception cref="InvalidOperationException">There are zero of more than one <see cref="SubstituteType"/>
/// objects in the <see cref="IArgumentNullExceptionFixture.Filters"/>.</exception>
private static SubstituteType GetSubstituteTypeMapping(this IArgumentNullExceptionFixture fixture)
{
if (fixture == null)
{
throw new ArgumentNullException(nameof(fixture));
}
SubstituteType substituteType =
fixture.Mappings
.OfType <SubstituteType>()
.SingleOrDefault();
if (substituteType == null)
{
throw new InvalidOperationException("There is no SubstituteType in the mappings.");
}
return(substituteType);
}
/// <summary>
/// 自定義HTML內容注入屬性構造函數
/// </summary>
/// <param name="source">注入點</param>
/// <param name="target">取得注入點</param>
public SubstituteAttribute(SubstituteType source, string target)
{
_source = source;
_target = target;
}