static StreamCloning()
{
// MemoryStream can be created from byte[] at non-zero origin offset which
// is not exposed via public APIs.
// TODO: handle the case when the method API is not available (e.g. copy buffer)
var internalGetOriginAndLength = typeof(MemoryStream).GetMethod(
"InternalGetOriginAndLength", BindingFlags.NonPublic | BindingFlags.Instance);
var stream = Expression.Parameter(typeof(MemoryStream));
var origin = Expression.Parameter(typeof(int).MakeByRefType());
var length = Expression.Parameter(typeof(int).MakeByRefType());
//internal method InternalGetOriginAndLength exists in .NET
if (internalGetOriginAndLength != null)
{
getOriginAndLength = Expression.Lambda <GetOriginAndLength>(
Expression.Call(stream, internalGetOriginAndLength, origin, length), stream, origin, length)
.Compile();
}
else
{
//Mono uses 'initialIndex' and 'length' fields in memory stream to handle the data
//see ref: https://github.com/mono/mono/blob/989301647e7cdf93acb69aacabcbb2bb2884e041/mcs/class/corlib/System.IO/MemoryStream.cs#L122-L126
var assign1 = Expression.Assign(origin, Expression.Field(stream, "initialIndex")); //origin = stream.initialIndex
var assign2 = Expression.Assign(length, Expression.Field(stream, "length")); //length = stream.length
getOriginAndLength = Expression.Lambda <GetOriginAndLength>(
Expression.Block(assign1, assign2), stream, origin, length)
.Compile();
}
}
static StreamCloning()
{
// MemoryStream can be created from byte[] at non-zero origin offset which
// is not exposed via public APIs.
// TODO: handle the case when the method API is not available (e.g. copy buffer)
var internalGetOriginAndLength = typeof(MemoryStream).GetMethod(
"InternalGetOriginAndLength", BindingFlags.NonPublic | BindingFlags.Instance);
var stream = Expression.Parameter(typeof(MemoryStream));
var origin = Expression.Parameter(typeof(int).MakeByRefType());
var length = Expression.Parameter(typeof(int).MakeByRefType());
//internal method InternalGetOriginAndLength exists in .NET
if (internalGetOriginAndLength != null)
{
getOriginAndLength = Expression.Lambda<GetOriginAndLength>(
Expression.Call(stream, internalGetOriginAndLength, origin, length), stream, origin, length)
.Compile();
}
else
{
//Mono uses 'initialIndex' and 'length' fields in memory stream to handle the data
//see ref: https://github.com/mono/mono/blob/989301647e7cdf93acb69aacabcbb2bb2884e041/mcs/class/corlib/System.IO/MemoryStream.cs#L122-L126
var assign1 = Expression.Assign(origin, Expression.Field(stream, "initialIndex")); //origin = stream.initialIndex
var assign2 = Expression.Assign(length, Expression.Field(stream, "length")); //length = stream.length
getOriginAndLength = Expression.Lambda<GetOriginAndLength>(
Expression.Block(assign1, assign2), stream, origin, length)
.Compile();
}
}
static StreamCloning()
{
// MemoryStream can be created from byte[] at non-zero origin offset which
// is not exposed via public APIs.
// TODO: handle the case when the method API is not available (e.g. copy buffer)
var internalGetOriginAndLength = typeof(MemoryStream).GetMethod(
"InternalGetOriginAndLength", BindingFlags.NonPublic | BindingFlags.Instance);
var stream = Expression.Parameter(typeof(MemoryStream));
var origin = Expression.Parameter(typeof(int).MakeByRefType());
var length = Expression.Parameter(typeof(int).MakeByRefType());
getOriginAndLength = Expression.Lambda <GetOriginAndLength>(
Expression.Call(stream, internalGetOriginAndLength, origin, length), stream, origin, length)
.Compile();
}
