JTokenReader
Represents a reader that provides fast, non-cached, forward-only access to serialized Json data.
using Newtonsoft.Json.Utilities;
using System;
namespace Newtonsoft.Json.Linq
{
public class JTokenReader : JsonReader, IJsonLineInfo
{
private readonly string _initialPath;
private readonly JToken _root;
private JToken _parent;
internal JToken _current;
private bool IsEndElement => _current == _parent;
int IJsonLineInfo.LineNumber {
get {
if (base.CurrentState == State.Start)
return 0;
return ((IJsonLineInfo)(IsEndElement ? null : _current))?.LineNumber ?? 0;
}
}
int IJsonLineInfo.LinePosition {
get {
if (base.CurrentState == State.Start)
return 0;
return ((IJsonLineInfo)(IsEndElement ? null : _current))?.LinePosition ?? 0;
}
}
public override string Path {
get {
string text = base.Path;
if (!string.IsNullOrEmpty(_initialPath)) {
if (string.IsNullOrEmpty(text))
return _initialPath;
text = ((!_initialPath.EndsWith("]", StringComparison.OrdinalIgnoreCase) && !text.StartsWith("[", StringComparison.OrdinalIgnoreCase)) ? (_initialPath + "." + text) : (_initialPath + text));
}
return text;
}
}
public JTokenReader(JToken token)
{
ValidationUtils.ArgumentNotNull(token, "token");
_root = token;
_current = token;
}
internal JTokenReader(JToken token, string initialPath)
: this(token)
{
_initialPath = initialPath;
}
public override byte[] ReadAsBytes()
{
return ReadAsBytesInternal();
}
public override decimal? ReadAsDecimal()
{
return ReadAsDecimalInternal();
}
public override int? ReadAsInt32()
{
return ReadAsInt32Internal();
}
public override string ReadAsString()
{
return ReadAsStringInternal();
}
public override DateTime? ReadAsDateTime()
{
return ReadAsDateTimeInternal();
}
public override DateTimeOffset? ReadAsDateTimeOffset()
{
return ReadAsDateTimeOffsetInternal();
}
internal override bool ReadInternal()
{
if (base.CurrentState != 0) {
JContainer jContainer = _current as JContainer;
if (jContainer != null && _parent != jContainer)
return ReadInto(jContainer);
return ReadOver(_current);
}
SetToken(_current);
return true;
}
public override bool Read()
{
_readType = ReadType.Read;
return ReadInternal();
}
private bool ReadOver(JToken t)
{
if (t == _root)
return ReadToEnd();
JToken next = t.Next;
if (next == null || next == t || t == t.Parent.Last) {
if (t.Parent == null)
return ReadToEnd();
return SetEnd(t.Parent);
}
_current = next;
SetToken(_current);
return true;
}
private bool ReadToEnd()
{
SetToken(JsonToken.None);
return false;
}
private JsonToken? GetEndToken(JContainer c)
{
switch (c.Type) {
case JTokenType.Object:
return JsonToken.EndObject;
case JTokenType.Array:
return JsonToken.EndArray;
case JTokenType.Constructor:
return JsonToken.EndConstructor;
case JTokenType.Property:
return null;
default:
throw MiscellaneousUtils.CreateArgumentOutOfRangeException("Type", c.Type, "Unexpected JContainer type.");
}
}
private bool ReadInto(JContainer c)
{
JToken first = c.First;
if (first == null)
return SetEnd(c);
SetToken(first);
_current = first;
_parent = c;
return true;
}
private bool SetEnd(JContainer c)
{
JsonToken? endToken = GetEndToken(c);
if (endToken.HasValue) {
SetToken(endToken.Value);
_current = c;
_parent = c;
return true;
}
return ReadOver(c);
}
private void SetToken(JToken token)
{
switch (token.Type) {
case JTokenType.Object:
SetToken(JsonToken.StartObject);
break;
case JTokenType.Array:
SetToken(JsonToken.StartArray);
break;
case JTokenType.Constructor:
SetToken(JsonToken.StartConstructor, ((JConstructor)token).Name);
break;
case JTokenType.Property:
SetToken(JsonToken.PropertyName, ((JProperty)token).Name);
break;
case JTokenType.Comment:
SetToken(JsonToken.Comment, ((JValue)token).Value);
break;
case JTokenType.Integer:
SetToken(JsonToken.Integer, ((JValue)token).Value);
break;
case JTokenType.Float:
SetToken(JsonToken.Float, ((JValue)token).Value);
break;
case JTokenType.String:
SetToken(JsonToken.String, ((JValue)token).Value);
break;
case JTokenType.Boolean:
SetToken(JsonToken.Boolean, ((JValue)token).Value);
break;
case JTokenType.Null:
SetToken(JsonToken.Null, ((JValue)token).Value);
break;
case JTokenType.Undefined:
SetToken(JsonToken.Undefined, ((JValue)token).Value);
break;
case JTokenType.Date:
SetToken(JsonToken.Date, ((JValue)token).Value);
break;
case JTokenType.Raw:
SetToken(JsonToken.Raw, ((JValue)token).Value);
break;
case JTokenType.Bytes:
SetToken(JsonToken.Bytes, ((JValue)token).Value);
break;
case JTokenType.Guid:
SetToken(JsonToken.String, SafeToString(((JValue)token).Value));
break;
case JTokenType.Uri:
SetToken(JsonToken.String, SafeToString(((JValue)token).Value));
break;
case JTokenType.TimeSpan:
SetToken(JsonToken.String, SafeToString(((JValue)token).Value));
break;
default:
throw MiscellaneousUtils.CreateArgumentOutOfRangeException("Type", token.Type, "Unexpected JTokenType.");
}
}
private string SafeToString(object value)
{
return value?.ToString();
}
bool IJsonLineInfo.HasLineInfo()
{
if (base.CurrentState == State.Start)
return false;
return ((IJsonLineInfo)(IsEndElement ? null : _current))?.HasLineInfo() ?? false;
}
}
}