private static JsonTokenType GetTokenType(string token)
{
//Prepare
JsonTokenType type = JsonTokenType.Literal;
using (JsonStringReader reader = new JsonStringReader(token))
{
switch (reader.PeekToken())
{
case '{': type = JsonTokenType.Collection; break;
case '[': type = JsonTokenType.Array; break;
case '"': type = JsonTokenType.String; break;
case '-':
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9': type = JsonTokenType.Number; break;
}
}
//Return
return(type);
}
/// <summary>
/// Converts the specified string to a JSON object.
/// </summary>
/// <param name="json">The JSON string. This value can be null.</param>
/// <returns>A JSON object representing the specified string.</returns>
public static JsonObject Parse(string json)
{
//Check
if (string.IsNullOrEmpty(json))
{
return(new JsonNull());
}
//Create reader
using (JsonStringReader reader = new JsonStringReader(json))
{
//Read first token
if (reader.PeekToken() == -1)
{
return(new JsonNull());
}
string token = reader.ReadToken();
//Check peek char
switch (GetTokenType(token))
{
case JsonTokenType.Number:
return(new JsonNumber()
{
Value = decimal.Parse(token)
});
case JsonTokenType.String:
return(new JsonString()
{
Value = FormatString(token)
});
case JsonTokenType.Collection:
JsonElementCollection collection = new JsonElementCollection();
using (JsonStringReader collectionReader = new JsonStringReader(token))
{
//Read open brace
collectionReader.Read();
//Loop
while (collectionReader.PeekToken() != '}')
{
//Read key-value pair
string nameToken = collectionReader.ReadString();
collectionReader.ReadToken();
string valueToken = collectionReader.ReadToken();
//Check
if (collectionReader.PeekToken() == ',')
{
collectionReader.ReadToken();
}
collection.Add(new JsonElement()
{
Name = FormatString(nameToken), Value = Parse(valueToken)
});
}
//Read close brace
collectionReader.Read();
}
return(collection);
case JsonTokenType.Array:
JsonObjectCollection array = new JsonObjectCollection();
using (JsonStringReader arrayReader = new JsonStringReader(token))
{
//Read open bracket
arrayReader.Read();
//Loop
while (arrayReader.PeekToken() != ']')
{
//Read object
string elementToken = arrayReader.ReadToken();
//Check
if (arrayReader.PeekToken() == ',')
{
arrayReader.ReadToken();
}
array.Add(Parse(elementToken));
}
//Read close bracket
arrayReader.Read();
}
return(array);
case JsonTokenType.Literal:
if (token == "true" || token == "false")
{
return new JsonBoolean()
{
Value = bool.Parse(token)
}
}
;
else if (token == "null")
{
return(new JsonNull());
}
throw new InvalidDataException("Only the 'true', 'false', and 'null' literals are supported.");
}
}
//Return
return(null);
}
