/// <summary>
/// 转换方法。
/// </summary>
/// <param name="obj">值</param>
/// <returns>返回新值</returns>
public static TDestination Convert(object obj)
{
if (obj == null)
{
return(XConvert <object, TDestination> .Convert(null));
}
if (obj is TDestination)
{
return((TDestination)obj);
}
var typeKey = (long)Pointer.GetTypeHandle(obj);
IDConvert <TDestination> value;
if (!Cache.TryGetValue(typeKey, out value))
{
lock (CacheLock)
{
if (!Cache.TryGetValue(typeKey, out value))
{
var type = typeof(XConvert <,>).MakeGenericType(obj.GetType(), typeof(TDestination));
value = (IDConvert <TDestination>)Activator.CreateInstance(type);
Cache.Add(typeKey, value);
}
}
}
return(value.Convert(obj));
}
private static void SwitchSequence <T>(this ILGenerator ilGen,
Action <ILGenerator> emitLoadValue,
CaseInfo <T>[] cases,
Label defaultLabel,
T offset = default)
{
emitLoadValue(ilGen);
if (!TypeHelper.IsEmptyValue(offset))
{
if (Underlying.SizeOf <T>() <= sizeof(int))
{
ilGen.LoadConstant(XConvert <int> .Convert(offset));
}
else
{
ilGen.LoadConstant(XConvert <long> .Convert(offset));
}
ilGen.Subtract();
}
ilGen.Switch(cases.Map(item => item.Label));
ilGen.Branch(defaultLabel);
}
/// <summary>
/// 创建 XConvert 类型转换迭代器。
/// </summary>
/// <typeparam name="TIn">输入类型</typeparam>
/// <typeparam name="TOut">输出类型</typeparam>
/// <param name="input">输入迭代器</param>
/// <returns>返回一个 yield 关键字实现的迭代器</returns>
public static IEnumerable <TOut> CreateAsIterator <TIn, TOut>(IEnumerable <TIn> input)
{
foreach (var item in input)
{
yield return(XConvert <TOut> .Convert(item));
}
}
public static TDestination?ConvertTo <TSource, TDestination>(TSource source) where TDestination : struct
{
if (source == null)
{
return(null);
}
return(XConvert <TSource, TDestination> .Convert(source));
}
public static TDestination Convert <TSource, TDestination>(TSource?source) where TSource : struct
{
if (source == null)
{
object nullValue = null;
return((TDestination)nullValue);
}
return(XConvert <TSource, TDestination> .Convert(source.Value));
}
private static bool IsSequence <T>(CaseInfo <T>[] cases, out T offset)
{
if (cases.Length > 0)
{
offset = cases[0].Value;
for (uint i = 0; i < cases.Length; i++)
{
if (XConvert <long> .Convert(offset) + i != XConvert <long> .Convert(cases[i].Value))
{
return(false);
}
}
return(true);
}
offset = default;
return(false);
}
public override TDestination Convert <TDestination>(object value) => XConvert <TDestination> .Convert((TSource)value);
public static TDestination Convert <TSource, TDestination>(TSource source)
{
return(XConvert <TSource, TDestination> .Convert(source));
}
public override object Convert <TSource>(TSource value) => XConvert <TDestination> .Convert(value);