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using System;
using System.Collections;
using System.Text;
using System.Collections.Generic;
/* Based on the JSON parser from
* http://techblog.procurios.nl/k/618/news/view/14605/14863/How-do-I-write-my-own-parser-for-JSON.html
*
* I simplified it so that it doesn't throw exceptions
* and can be used in Unity iPhone with maximum code stripping.
*/
/// <summary>
/// This class encodes and decodes JSON strings.
/// Spec. details, see http://www.json.org/
///
/// JSON uses Arrays and Objects. These correspond here to the datatypes ArrayList and Hashtable.
/// All numbers are parsed to doubles.
/// </summary>
public class MiniJSON
{
private const int TOKEN_NONE = 0;
private const int TOKEN_CURLY_OPEN = 1;
private const int TOKEN_CURLY_CLOSE = 2;
private const int TOKEN_SQUARED_OPEN = 3;
private const int TOKEN_SQUARED_CLOSE = 4;
private const int TOKEN_COLON = 5;
private const int TOKEN_COMMA = 6;
private const int TOKEN_STRING = 7;
private const int TOKEN_NUMBER = 8;
private const int TOKEN_TRUE = 9;
private const int TOKEN_FALSE = 10;
private const int TOKEN_NULL = 11;
private const int BUILDER_CAPACITY = 2000;
/// <summary>
/// On decoding, this value holds the position at which the parse failed (-1 = no error).
/// </summary>
protected static int lastErrorIndex = -1;
protected static string lastDecode = "";
/// <summary>
/// Parses the string json into a value
/// </summary>
/// <param name="json">A JSON string.</param>
/// <returns>An ArrayList, a Hashtable, a double, a string, null, true, or false</returns>
public static object jsonDecode( string json )
{
// save the string for debug information
MiniJSON.lastDecode = json;
if( json != null )
{
char[] charArray = json.ToCharArray();
int index = 0;
bool success = true;
object value = MiniJSON.parseValue( charArray, ref index, ref success );
if( success )
MiniJSON.lastErrorIndex = -1;
else
MiniJSON.lastErrorIndex = index;
return value;
}
else
{
return null;
}
}
/// <summary>
/// Converts a Hashtable / ArrayList / Dictionary(string,string) object into a JSON string
/// </summary>
/// <param name="json">A Hashtable / ArrayList</param>
/// <returns>A JSON encoded string, or null if object 'json' is not serializable</returns>
public static string jsonEncode( object json )
{
var builder = new StringBuilder( BUILDER_CAPACITY );
var success = MiniJSON.serializeValue( json, builder );
return ( success ? builder.ToString() : null );
}
/// <summary>
/// On decoding, this function returns the position at which the parse failed (-1 = no error).
/// </summary>
/// <returns></returns>
public static bool lastDecodeSuccessful()
{
return ( MiniJSON.lastErrorIndex == -1 );
}
/// <summary>
/// On decoding, this function returns the position at which the parse failed (-1 = no error).
/// </summary>
/// <returns></returns>
public static int getLastErrorIndex()
{
return MiniJSON.lastErrorIndex;
}
/// <summary>
/// If a decoding error occurred, this function returns a piece of the JSON string
/// at which the error took place. To ease debugging.
/// </summary>
/// <returns></returns>
public static string getLastErrorSnippet()
{
if( MiniJSON.lastErrorIndex == -1 )
{
return "";
}
else
{
int startIndex = MiniJSON.lastErrorIndex - 5;
int endIndex = MiniJSON.lastErrorIndex + 15;
if( startIndex < 0 )
startIndex = 0;
if( endIndex >= MiniJSON.lastDecode.Length )
endIndex = MiniJSON.lastDecode.Length - 1;
return MiniJSON.lastDecode.Substring( startIndex, endIndex - startIndex + 1 );
}
}
#region Parsing
protected static Hashtable parseObject( char[] json, ref int index )
{
Hashtable table = new Hashtable();
int token;
// {
nextToken( json, ref index );
bool done = false;
while( !done )
{
token = lookAhead( json, index );
if( token == MiniJSON.TOKEN_NONE )
{
return null;
}
else if( token == MiniJSON.TOKEN_COMMA )
{
nextToken( json, ref index );
}
else if( token == MiniJSON.TOKEN_CURLY_CLOSE )
{
nextToken( json, ref index );
return table;
}
else
{
// name
string name = parseString( json, ref index );
if( name == null )
{
return null;
}
// :
token = nextToken( json, ref index );
if( token != MiniJSON.TOKEN_COLON )
return null;
// value
bool success = true;
object value = parseValue( json, ref index, ref success );
if( !success )
return null;
table[name] = value;
}
}
return table;
}
protected static ArrayList parseArray( char[] json, ref int index )
{
ArrayList array = new ArrayList();
// [
nextToken( json, ref index );
bool done = false;
while( !done )
{
int token = lookAhead( json, index );
if( token == MiniJSON.TOKEN_NONE )
{
return null;
}
else if( token == MiniJSON.TOKEN_COMMA )
{
nextToken( json, ref index );
}
else if( token == MiniJSON.TOKEN_SQUARED_CLOSE )
{
nextToken( json, ref index );
break;
}
else
{
bool success = true;
object value = parseValue( json, ref index, ref success );
if( !success )
return null;
array.Add( value );
}
}
return array;
}
protected static object parseValue( char[] json, ref int index, ref bool success )
{
switch( lookAhead( json, index ) )
{
case MiniJSON.TOKEN_STRING:
return parseString( json, ref index );
case MiniJSON.TOKEN_NUMBER:
return parseNumber( json, ref index );
case MiniJSON.TOKEN_CURLY_OPEN:
return parseObject( json, ref index );
case MiniJSON.TOKEN_SQUARED_OPEN:
return parseArray( json, ref index );
case MiniJSON.TOKEN_TRUE:
nextToken( json, ref index );
return Boolean.Parse( "TRUE" );
case MiniJSON.TOKEN_FALSE:
nextToken( json, ref index );
return Boolean.Parse( "FALSE" );
case MiniJSON.TOKEN_NULL:
nextToken( json, ref index );
return null;
case MiniJSON.TOKEN_NONE:
break;
}
success = false;
return null;
}
protected static string parseString( char[] json, ref int index )
{
string s = "";
char c;
eatWhitespace( json, ref index );
// "
c = json[index++];
bool complete = false;
while( !complete )
{
if( index == json.Length )
break;
c = json[index++];
if( c == '"' )
{
complete = true;
break;
}
else if( c == '\\' )
{
if( index == json.Length )
break;
c = json[index++];
if( c == '"' )
{
s += '"';
}
else if( c == '\\' )
{
s += '\\';
}
else if( c == '/' )
{
s += '/';
}
else if( c == 'b' )
{
s += '\b';
}
else if( c == 'f' )
{
s += '\f';
}
else if( c == 'n' )
{
s += '\n';
}
else if( c == 'r' )
{
s += '\r';
}
else if( c == 't' )
{
s += '\t';
}
else if( c == 'u' )
{
int remainingLength = json.Length - index;
if( remainingLength >= 4 )
{
char[] unicodeCharArray = new char[4];
Array.Copy( json, index, unicodeCharArray, 0, 4 );
// Drop in the HTML markup for the unicode character
s += "&#x" + new string( unicodeCharArray ) + ";";
/*
uint codePoint = UInt32.Parse(new string(unicodeCharArray), NumberStyles.HexNumber);
// convert the integer codepoint to a unicode char and add to string
s += Char.ConvertFromUtf32((int)codePoint);
*/
// skip 4 chars
index += 4;
}
else
{
break;
}
}
}
else
{
s += c;
}
}
if( !complete )
return null;
return s;
}
protected static double parseNumber( char[] json, ref int index )
{
eatWhitespace( json, ref index );
int lastIndex = getLastIndexOfNumber( json, index );
int charLength = ( lastIndex - index ) + 1;
char[] numberCharArray = new char[charLength];
Array.Copy( json, index, numberCharArray, 0, charLength );
index = lastIndex + 1;
return Double.Parse( new string( numberCharArray ) ); // , CultureInfo.InvariantCulture);
}
protected static int getLastIndexOfNumber( char[] json, int index )
{
int lastIndex;
for( lastIndex = index; lastIndex < json.Length; lastIndex++ )
if( "0123456789+-.eE".IndexOf( json[lastIndex] ) == -1 )
{
break;
}
return lastIndex - 1;
}
protected static void eatWhitespace( char[] json, ref int index )
{
for( ; index < json.Length; index++ )
if( " \t\n\r".IndexOf( json[index] ) == -1 )
{
break;
}
}
protected static int lookAhead( char[] json, int index )
{
int saveIndex = index;
return nextToken( json, ref saveIndex );
}
protected static int nextToken( char[] json, ref int index )
{
eatWhitespace( json, ref index );
if( index == json.Length )
{
return MiniJSON.TOKEN_NONE;
}
char c = json[index];
index++;
switch( c )
{
case '{':
return MiniJSON.TOKEN_CURLY_OPEN;
case '}':
return MiniJSON.TOKEN_CURLY_CLOSE;
case '[':
return MiniJSON.TOKEN_SQUARED_OPEN;
case ']':
return MiniJSON.TOKEN_SQUARED_CLOSE;
case ',':
return MiniJSON.TOKEN_COMMA;
case '"':
return MiniJSON.TOKEN_STRING;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
case '-':
return MiniJSON.TOKEN_NUMBER;
case ':':
return MiniJSON.TOKEN_COLON;
}
index--;
int remainingLength = json.Length - index;
// false
if( remainingLength >= 5 )
{
if( json[index] == 'f' &&
json[index + 1] == 'a' &&
json[index + 2] == 'l' &&
json[index + 3] == 's' &&
json[index + 4] == 'e' )
{
index += 5;
return MiniJSON.TOKEN_FALSE;
}
}
// true
if( remainingLength >= 4 )
{
if( json[index] == 't' &&
json[index + 1] == 'r' &&
json[index + 2] == 'u' &&
json[index + 3] == 'e' )
{
index += 4;
return MiniJSON.TOKEN_TRUE;
}
}
// null
if( remainingLength >= 4 )
{
if( json[index] == 'n' &&
json[index + 1] == 'u' &&
json[index + 2] == 'l' &&
json[index + 3] == 'l' )
{
index += 4;
return MiniJSON.TOKEN_NULL;
}
}
return MiniJSON.TOKEN_NONE;
}
#endregion
#region Serialization
protected static bool serializeObjectOrArray( object objectOrArray, StringBuilder builder )
{
if( objectOrArray is Hashtable )
{
return serializeObject( (Hashtable)objectOrArray, builder );
}
else if( objectOrArray is ArrayList )
{
return serializeArray( (ArrayList)objectOrArray, builder );
}
else
{
return false;
}
}
protected static bool serializeObject( Hashtable anObject, StringBuilder builder )
{
builder.Append( "{" );
IDictionaryEnumerator e = anObject.GetEnumerator();
bool first = true;
while( e.MoveNext() )
{
string key = e.Key.ToString();
object value = e.Value;
if( !first )
{
builder.Append( ", " );
}
serializeString( key, builder );
builder.Append( ":" );
if( !serializeValue( value, builder ) )
{
return false;
}
first = false;
}
builder.Append( "}" );
return true;
}
protected static bool serializeDictionary( Dictionary<string,string> dict, StringBuilder builder )
{
builder.Append( "{" );
bool first = true;
foreach( var kv in dict )
{
if( !first )
builder.Append( ", " );
serializeString( kv.Key, builder );
builder.Append( ":" );
serializeString( kv.Value, builder );
first = false;
}
builder.Append( "}" );
return true;
}
protected static bool serializeArray( ArrayList anArray, StringBuilder builder )
{
builder.Append( "[" );
bool first = true;
for( int i = 0; i < anArray.Count; i++ )
{
object value = anArray[i];
if( !first )
{
builder.Append( ", " );
}
if( !serializeValue( value, builder ) )
{
return false;
}
first = false;
}
builder.Append( "]" );
return true;
}
protected static bool serializeValue( object value, StringBuilder builder )
{
// Type t = value.GetType();
// Debug.Log("type: " + t.ToString() + " isArray: " + t.IsArray);
if( value == null )
{
builder.Append( "null" );
}
else if( value.GetType().IsArray )
{
serializeArray( new ArrayList( (ICollection)value ), builder );
}
else if( value is string )
{
serializeString( (string)value, builder );
}
else if( value is Char )
{
serializeString( Convert.ToString( (char)value ), builder );
}
else if( value is Hashtable )
{
serializeObject( (Hashtable)value, builder );
}
else if( value is Dictionary<string,string> )
{
serializeDictionary( (Dictionary<string,string>)value, builder );
}
else if( value is ArrayList )
{
serializeArray( (ArrayList)value, builder );
}
else if( ( value is Boolean ) && ( (Boolean)value == true ) )
{
builder.Append( "true" );
}
else if( ( value is Boolean ) && ( (Boolean)value == false ) )
{
builder.Append( "false" );
}
else if( value.GetType().IsPrimitive )
{
serializeNumber( Convert.ToDouble( value ), builder );
}
else
{
return false;
}
return true;
}
protected static void serializeString( string aString, StringBuilder builder )
{
builder.Append( "\"" );
char[] charArray = aString.ToCharArray();
for( int i = 0; i < charArray.Length; i++ )
{
char c = charArray[i];
if( c == '"' )
{
builder.Append( "\\\"" );
}
else if( c == '\\' )
{
builder.Append( "\\\\" );
}
else if( c == '\b' )
{
builder.Append( "\\b" );
}
else if( c == '\f' )
{
builder.Append( "\\f" );
}
else if( c == '\n' )
{
builder.Append( "\\n" );
}
else if( c == '\r' )
{
builder.Append( "\\r" );
}
else if( c == '\t' )
{
builder.Append( "\\t" );
}
else
{
int codepoint = Convert.ToInt32( c );
if( ( codepoint >= 32 ) && ( codepoint <= 126 ) )
{
builder.Append( c );
}
else
{
builder.Append( "\\u" + Convert.ToString( codepoint, 16 ).PadLeft( 4, '0' ) );
}
}
}
builder.Append( "\"" );
}
protected static void serializeNumber( double number, StringBuilder builder )
{
builder.Append( Convert.ToString( number ) ); // , CultureInfo.InvariantCulture));
}
#endregion
}
#region Extension methods
public static class MiniJsonExtensions
{
public static string toJson( this Hashtable obj )
{
return MiniJSON.jsonEncode( obj );
}
public static string toJson( this Dictionary<string,string> obj )
{
return MiniJSON.jsonEncode( obj );
}
public static ArrayList arrayListFromJson( this string json )
{
return MiniJSON.jsonDecode( json ) as ArrayList;
}
public static Hashtable hashtableFromJson( this string json )
{
return MiniJSON.jsonDecode( json ) as Hashtable;
}
}
#endregion