public static bool TryFormat(this char value, Span<byte> buffer, Format.Parsed format, EncodingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
if (buffer.Length < 2)
{
bytesWritten = 0;
return false;
}
buffer[0] = (byte)value;
buffer[1] = (byte)(value >> 8);
bytesWritten = 2;
return true;
}
if (buffer.Length < 1)
{
bytesWritten = 0;
return false;
}
// fast path for ASCII
if (value <= 127)
{
buffer[0] = (byte)value;
bytesWritten = 1;
return true;
}
// TODO: This can be directly encoded to SpanByte. There is no conversion between spans yet
var encoded = new Utf8EncodedCodePoint(value);
bytesWritten = encoded.Length;
if (buffer.Length < bytesWritten)
{
bytesWritten = 0;
return false;
}
buffer[0] = encoded.Byte0;
if(bytesWritten > 1)
{
buffer[1] = encoded.Byte1;
}
if(bytesWritten > 2)
{
buffer[2] = encoded.Byte2;
}
if(bytesWritten > 3)
{
buffer[3] = encoded.Byte3;
}
return true;
}
public static bool TryEncode(this char value, Span<byte> buffer, out int bytesWritten, TextEncoding encoding = TextEncoding.Utf8)
{
if (encoding == TextEncoding.Utf16)
{
if (buffer.Length < 2)
{
bytesWritten = 0;
return false;
}
buffer[0] = (byte)value;
buffer[1] = (byte)(value >> 8);
bytesWritten = 2;
return true;
}
if (encoding == TextEncoding.Utf8) {
if (buffer.Length < 1) {
bytesWritten = 0;
return false;
}
// fast path for ASCII
if (value <= 127) {
buffer[0] = (byte)value;
bytesWritten = 1;
return true;
}
// TODO: This can be directly encoded to SpanByte. There is no conversion between spans yet
var encoded = new Utf8EncodedCodePoint(value);
bytesWritten = encoded.Length;
if (buffer.Length < bytesWritten) {
bytesWritten = 0;
return false;
}
buffer[0] = encoded.Byte0;
if (bytesWritten > 1) {
buffer[1] = encoded.Byte1;
}
if (bytesWritten > 2) {
buffer[2] = encoded.Byte2;
}
if (bytesWritten > 3) {
buffer[3] = encoded.Byte3;
}
return true;
}
throw new NotImplementedException();
}
public override bool TryEncodeChar(char value, Span <byte> buffer, out int bytesWritten)
{
if (buffer.Length < 1)
{
bytesWritten = 0;
return(false);
}
// fast path for ASCII
if (value <= 127)
{
buffer[0] = (byte)value;
bytesWritten = 1;
return(true);
}
// TODO: This can be directly encoded to SpanByte. There is no conversion between spans yet
var encoded = new Utf8EncodedCodePoint(value);
bytesWritten = encoded.Length;
if (buffer.Length < bytesWritten)
{
bytesWritten = 0;
return(false);
}
buffer[0] = encoded.Byte0;
if (bytesWritten > 1)
{
buffer[1] = encoded.Byte1;
}
if (bytesWritten > 2)
{
buffer[2] = encoded.Byte2;
}
if (bytesWritten > 3)
{
buffer[3] = encoded.Byte3;
}
return(true);
}
public static bool TryFormat(this string value, Span<byte> buffer, Format.Parsed format, EncodingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
var valueBytes = value.Length << 1;
if (valueBytes > buffer.Length)
{
bytesWritten = 0;
return false;
}
unsafe
{
fixed (char* pCharacters = value)
{
byte* pBytes = (byte*)pCharacters;
buffer.Set(pBytes, valueBytes);
}
}
bytesWritten = valueBytes;
return true;
}
var avaliableBytes = buffer.Length;
bytesWritten = 0;
for (int i = 0; i < value.Length; i++)
{
var c = value[i];
var codepoint = (ushort)c;
if (codepoint <= 0x7f) // this if block just optimizes for ascii
{
if (bytesWritten + 1 > avaliableBytes)
{
bytesWritten = 0;
return false;
}
buffer[bytesWritten++] = (byte)codepoint;
}
else
{
Utf8EncodedCodePoint encoded;
if (!char.IsSurrogate(c))
encoded = new Utf8EncodedCodePoint(c);
else
{
if (++i >= value.Length)
throw new ArgumentException("Invalid surrogate pair.", nameof(value));
char lowSurrogate = value[i];
encoded = new Utf8EncodedCodePoint(c, lowSurrogate);
}
if (bytesWritten + encoded.Length > avaliableBytes)
{
bytesWritten = 0;
return false;
}
buffer[bytesWritten] = encoded.Byte0;
if (encoded.Length > 1)
{
buffer[bytesWritten + 1] = encoded.Byte1;
if (encoded.Length > 2)
{
buffer[bytesWritten + 2] = encoded.Byte2;
if (encoded.Length > 3)
{
buffer[bytesWritten + 3] = encoded.Byte3;
}
}
}
bytesWritten += encoded.Length;
}
}
return true;
}
public void Utf8EncodedCodePointFromChar7()
{
Utf8EncodedCodePoint ecp = new Utf8EncodedCodePoint('\uFFFF');
Assert.Equal(3, ecp.Length);
Assert.Equal(0xEF, ecp.Byte0);
Assert.Equal(0xBF, ecp.Byte1);
Assert.Equal(0xBF, ecp.Byte2);
}
public void Utf8EncodedCodePointFromChar6()
{
Utf8EncodedCodePoint ecp = new Utf8EncodedCodePoint('\u1FA9');
Assert.Equal(3, ecp.Length);
Assert.Equal(0xE1, ecp.Byte0);
Assert.Equal(0xBE, ecp.Byte1);
Assert.Equal(0xA9, ecp.Byte2);
}
public void Utf8EncodedCodePointFromChar5()
{
Utf8EncodedCodePoint ecp = new Utf8EncodedCodePoint('\u0800');
Assert.Equal(3, ecp.Length);
Assert.Equal(0xE0, ecp.Byte0);
Assert.Equal(0xA0, ecp.Byte1);
Assert.Equal(0x80, ecp.Byte2);
}
public void Utf8EncodedCodePointFromChar4()
{
Utf8EncodedCodePoint ecp = new Utf8EncodedCodePoint('\u07FF');
Assert.Equal(2, ecp.Length);
Assert.Equal(0xDF, ecp.Byte0);
Assert.Equal(0xBF, ecp.Byte1);
}
public void Utf8EncodedCodePointFromChar3()
{
Utf8EncodedCodePoint ecp = new Utf8EncodedCodePoint('\u01ED');
Assert.Equal(2, ecp.Length);
Assert.Equal(0xC7, ecp.Byte0);
Assert.Equal(0xAD, ecp.Byte1);
}
public void Utf8EncodedCodePointFromChar2()
{
Utf8EncodedCodePoint ecp = new Utf8EncodedCodePoint('\u0080');
Assert.Equal(2, ecp.Length);
Assert.Equal(0xC2, ecp.Byte0);
Assert.Equal(0x80, ecp.Byte1);
}
public void Utf8EncodedCodePointFromChar1()
{
Utf8EncodedCodePoint ecp = new Utf8EncodedCodePoint('\u007F');
Assert.Equal(1, ecp.Length);
Assert.Equal(0x7F, ecp.Byte0);
}
public static bool TryFormat(this string value, Span<byte> buffer, Format.Parsed format, FormattingData formattingData, out int bytesWritten)
{
if (formattingData.IsUtf16)
{
var valueBytes = value.Length << 1;
if (valueBytes > buffer.Length)
{
bytesWritten = 0;
return false;
}
unsafe
{
fixed (char* pCharacters = value)
{
byte* pBytes = (byte*)pCharacters;
buffer.Set(pBytes, valueBytes);
}
}
bytesWritten = valueBytes;
return true;
}
GCHandle handle;
var byteSpan = buffer.Pin(out handle);
try {
var avaliableBytes = byteSpan.Length;
bytesWritten = 0;
for (int i = 0; i < value.Length; i++)
{
var c = value[i];
var codepoint = (ushort)c;
if (codepoint <= 0x7f) // this if block just optimizes for ascii
{
if (bytesWritten + 1 > avaliableBytes)
{
bytesWritten = 0;
return false;
}
byteSpan[bytesWritten++] = (byte)codepoint;
}
else
{
var encoded = new Utf8EncodedCodePoint(c);
if (bytesWritten + encoded.Length > avaliableBytes)
{
bytesWritten = 0;
return false;
}
byteSpan[bytesWritten] = encoded.Byte0;
if (encoded.Length > 1)
{
byteSpan[bytesWritten + 1] = encoded.Byte1;
if (encoded.Length > 2)
{
byteSpan[bytesWritten + 2] = encoded.Byte2;
if (encoded.Length > 3)
{
byteSpan[bytesWritten + 3] = encoded.Byte3;
}
}
}
bytesWritten += encoded.Length;
}
}
return true;
}
finally
{
handle.Free();
}
}
public static bool TryEncode(this ReadOnlySpan<char> value, Span<byte> buffer, out int bytesWritten, TextEncoding encoding = TextEncoding.Utf8)
{
if (encoding == TextEncoding.Utf16) {
var valueBytes = value.Cast<char, byte>();
if (buffer.Length < valueBytes.Length) {
bytesWritten = 0;
return false;
}
valueBytes.CopyTo(buffer);
bytesWritten = valueBytes.Length;
return true;
}
if (encoding == TextEncoding.Utf8) {
var avaliableBytes = buffer.Length;
bytesWritten = 0;
for (int i = 0; i < value.Length; i++) {
var c = value[i];
var codepoint = (ushort)c;
if (codepoint <= 0x7f) // this if block just optimizes for ascii
{
if (bytesWritten + 1 > avaliableBytes) {
bytesWritten = 0;
return false;
}
buffer[bytesWritten++] = (byte)codepoint;
}
else {
Utf8EncodedCodePoint encoded;
if (!char.IsSurrogate(c))
encoded = new Utf8EncodedCodePoint(c);
else {
if (++i >= value.Length)
throw new ArgumentException("Invalid surrogate pair.", nameof(value));
char lowSurrogate = value[i];
encoded = new Utf8EncodedCodePoint(c, lowSurrogate);
}
if (bytesWritten + encoded.Length > avaliableBytes) {
bytesWritten = 0;
return false;
}
buffer[bytesWritten] = encoded.Byte0;
if (encoded.Length > 1) {
buffer[bytesWritten + 1] = encoded.Byte1;
if (encoded.Length > 2) {
buffer[bytesWritten + 2] = encoded.Byte2;
if (encoded.Length > 3) {
buffer[bytesWritten + 3] = encoded.Byte3;
}
}
}
bytesWritten += encoded.Length;
}
}
return true;
}
throw new NotSupportedException();
}
