/// <summary>
/// Parses a JSON snippet of an array value.
/// </summary>
/// <typeparam name="T">The type of the object to parse the array items into.</typeparam>
/// <param name="json">The string containing the JSON snippet, begining and ending with square brackets.</param>
/// <param name="typeResolver">A class to help resolving dynamic or unknown types.</param>
/// <returns>The parsed array.</returns>
public static T[] LoadArray <T>(string json, JsonTypeResolver typeResolver)
{
int i = 0;
IList list = ReadArray(json, ref i, typeof(T[]), typeResolver ?? JsonTypeResolver.FromAssemblyMappings <T>(), true);
T[] array = new T[list.Count];
list.CopyTo(array, 0);
return(array);
}
private static List <object> ReadArray(string s, ref int i, Type expectedValueType, JsonTypeResolver typeResolver, bool standalone = false)
{
global::System.Diagnostics.Debug.Assert(s != null);
global::System.Diagnostics.Debug.Assert(i >= 0 && i < s.Length);
global::System.Diagnostics.Debug.Assert(s[i] == '[');
List <object> values = new List <object>();
Type expectedArrayValueType = null;
if (expectedValueType != null)
{
Type[] listTypes;
if (expectedValueType.HasElementType)
{
expectedArrayValueType = expectedValueType.GetElementType();
}
else if (expectedValueType.Implements(typeof(IList <>), out listTypes))
{
expectedArrayValueType = listTypes[0].GenericTypeArguments[0];
}
}
++i;
EnsureNotEndOfString(s, i);
SkipWhitespace(s, ref i);
if (s[i] != ']')
{
while (true)
{
object arrayValue = ReadValue(s, ref i, null, expectedArrayValueType, typeResolver);
values.Add(arrayValue);
SkipWhitespace(s, ref i);
if (s[i] == ']')
{
break;
}
ReadNextMemberSeparator(s, ref i);
SkipWhitespace(s, ref i);
}
}
++i;
//if (!standalone)
// EnsureNotEndOfString(s, i);
return(values);
}
private static object ReadValue(string s, ref int i, object value, Type expectedValueType, JsonTypeResolver typeResolver)
{
JsonValueType jsonType = ReadValueType(s, ref i);
switch (jsonType)
{
case JsonValueType.String:
value = ReadString(s, ref i);
break;
case JsonValueType.Number:
value = ReadNumber(s, ref i);
break;
case JsonValueType.Object:
if (value == null)
{
if (expectedValueType != null)
{
ConstructorInfo memberCtor = expectedValueType.GetConstructor(new Type[0]);
if (memberCtor == null)
{
throw new FormatException("A type with parameter-less constructor is required at position " + i + ". If not available, supply an instance as the member's value.");
}
value = memberCtor.Invoke(null);
}
else
{
value = new Dictionary <string, object>();
}
}
LoadFromJson(value, s, ref i, typeResolver);
break;
case JsonValueType.Array:
List <object> arrayValues = ReadArray(s, ref i, expectedValueType, typeResolver);
if (expectedValueType != null && expectedValueType.IsArray)
{
Array array = Array.CreateInstance(expectedValueType.GetElementType(), arrayValues.Count);
object[] genericArray = arrayValues.ToArray();
genericArray.CopyTo(array, 0);
value = array;
}
else if (value is IList)
{
IList valueList = (IList)value;
try
{
valueList.Clear();
foreach (object arrayValue in arrayValues)
{
valueList.Add(arrayValue);
}
}
catch (Exception e)
{
global::System.Diagnostics.Debug.WriteLine("Array values could not be loaded at position {0}. Skipping. ({1})", i, e.Message);
}
}
else if (expectedValueType == null || expectedValueType.IsAssignableFrom(typeof(IList)))
{
value = arrayValues;
}
else if (expectedValueType.Implements <IList>())
{
ConstructorInfo memberCtor = expectedValueType.GetConstructor(new Type[0]);
if (memberCtor == null)
{
throw new FormatException("A type with parameter-less constructor is required at position " + i + ". If not available, supply an instance as the member's value.");
}
IList valueList = (IList)memberCtor.Invoke(null);
try
{
valueList.Clear();
foreach (object arrayValue in arrayValues)
{
valueList.Add(arrayValue);
}
}
catch (Exception e)
{
global::System.Diagnostics.Debug.WriteLine("Array values could not be loaded at position {0}. Skipping. ({1})", i, e.Message);
}
value = valueList;
}
else
{
throw new NotSupportedException("'" + expectedValueType + "' is not a supported type for loading array values.");
}
break;
case JsonValueType.True:
value = true;
break;
case JsonValueType.False:
value = false;
break;
case JsonValueType.Null:
value = null;
break;
default:
throw new NotSupportedException("Unsupported JSON type.");
}
return(value);
}
/// <summary>
/// Parses a JSON snippet of a value.
/// </summary>
/// <typeparam name="T">The type of the object to parse.</typeparam>
/// <param name="json">The string containing the JSON snippet.</param>
/// <param name="typeResolver">A class to help resolving dynamic or unknown types.</param>
/// <returns>The parsed value.</returns>
public static T LoadObject <T>(string json, JsonTypeResolver typeResolver) where T : new()
{
int i = 0;
return((T)ReadValue(json, ref i, null, typeof(T), typeResolver ?? JsonTypeResolver.FromAssemblyMappings <T>()));
}
private static void LoadFromJson <T>(T target, string json, ref int i, JsonTypeResolver typeResolver)
{
if (target == null)
{
throw new ArgumentNullException("target");
}
if (json == null)
{
throw new ArgumentNullException("json");
}
Type targetType = typeof(T);
if (target != null)
{
targetType = target.GetType();
}
IDictionary <string, PropertyInfo> memberResolver = GetAttributeMemberResolver(targetType);
List <ResolverPending> resolverPendings = new List <ResolverPending>();
SkipWhitespace(json, ref i);
ReadObjectStart(json, ref i);
do
{
SkipWhitespace(json, ref i);
if (json[i] == '}')
{
break;
}
string memberName = ReadMemberName(json, ref i);
SkipWhitespace(json, ref i);
ReadMemberValueSeparator(json, ref i);
SkipWhitespace(json, ref i);
if (target is IDictionary)
{
IDictionary targetTable = (IDictionary)target;
Type expectedTableValueType = null;
if (targetTable is TypeInKeyHashtable)
{
expectedTableValueType = typeResolver.ResolveType(memberName);
}
targetTable.Add(memberName, ReadValue(json, ref i, null, expectedTableValueType, typeResolver));
goto nextMember;
}
PropertyInfo memberProperty = null;
memberResolver.TryGetValue(memberName, out memberProperty);
pendingMember:
if (memberProperty == null || memberProperty.GetIndexParameters().Length > 0)
{
global::System.Diagnostics.Debug.WriteLine("JSON Parser: Member '{0}' not found on the object of type '{1}' or requires indices. Skipping.", memberName, targetType);
ReadValue(json, ref i, null, null, typeResolver);
goto nextMember;
}
Type expectedValueType = memberProperty.PropertyType;
if (typeResolver != null)
{
foreach (JsonMemberTypeInAttribute attribute in memberProperty.GetCustomAttributes <JsonMemberTypeInAttribute>(true))
{
PropertyInfo typeProperty = targetType.GetProperty(attribute.MemberName);
if (typeProperty != null)
{
if (typeProperty.PropertyType == typeof(Type))
{
expectedValueType = (Type)typeProperty.GetValue(target, null);
}
else if (typeProperty.PropertyType == typeof(string))
{
expectedValueType = typeResolver.ResolveType((string)typeProperty.GetValue(target, null)); // ?? memberProperty.PropertyType;
}
if (expectedValueType == null)
{
ResolverPending pending = new ResolverPending {
TypeProperty = typeProperty, MemberProperty = memberProperty, I = i
};
if (!resolverPendings.Any(p => p == pending))
{
resolverPendings.Add(pending);
}
ReadValue(json, ref i, null, null, null);
goto nextMember;
}
}
else
{
global::System.Diagnostics.Debug.WriteLine("Type property '{0}' not found on object of type '{1}'. Ignoring attribute.", attribute.MemberName, targetType.Name);
}
}
}
if (expectedValueType.Implements <IDictionary>() && memberProperty.GetCustomAttributes <JsonMemberTypeInKeyAttribute>(true).Any())
{
expectedValueType = typeof(TypeInKeyHashtable);
}
object currentValue = memberProperty.CanRead ? memberProperty.GetValue(target, null) : null;
object value = ReadValue(json, ref i, currentValue, expectedValueType, typeResolver);
if (!memberProperty.CanWrite)
{
if (value != currentValue)
{
global::System.Diagnostics.Debug.WriteLine("Member '{0}' is read-only. Skipping.", memberName);
}
goto nextMember;
}
if (value != null)
{
Type valueType = value.GetType();
if (!memberProperty.PropertyType.IsAssignableFrom(valueType))
{
try { value = System.Convert.ChangeType(value, memberProperty.PropertyType, Thread.CurrentThread.CurrentCulture); }
catch (Exception e)
{
global::System.Diagnostics.Debug.WriteLine("Invalid value for member '{0}' of type '{1}'. Skipping. ({2})", memberName, value, e.Message);
goto nextMember;
}
}
}
try
{
object oldValue = memberProperty.GetValue(target, null);
memberProperty.SetValue(target, value, null);
ResolverPending pending = resolverPendings.FirstOrDefault(p => p.TypeProperty == memberProperty);
if (pending != null)
{
resolverPendings.Remove(pending);
if (!object.Equals(oldValue, value))
{
i = pending.I;
memberProperty = pending.MemberProperty;
global::System.Diagnostics.Debug.WriteLine("Second pass for resolving value type for '{0}'.", memberProperty);
goto pendingMember;
}
else
{
global::System.Diagnostics.Debug.WriteLine("Value type for '{0}' cannot be resolved. Skipping.", memberProperty);
}
}
}
catch (Exception e)
{
global::System.Diagnostics.Debug.WriteLine("Cannot set value '{0}' to member '{1}'. Skipping. ({2}).", value, memberName, e.Message);
goto nextMember;
}
nextMember:
SkipWhitespace(json, ref i);
if (json[i] == '}')
{
break;
}
else if (json[i] != ',')
{
throw new FormatException("Unexpected character '" + json[i] + "' at position " + i + ".");
}
++i;
} while (true);
++i; // move after curly bracket
foreach (ResolverPending pending in resolverPendings)
{
global::System.Diagnostics.Debug.WriteLine("Cannot set value '{0}' because the expected type in '{1}' was not supplied. Skipping.", pending.MemberProperty, pending.TypeProperty);
}
}
/// <summary>
/// Parses a JSON string into an existing object.
/// </summary>
/// <typeparam name="T">The type of the object to parse the JSON string into.</typeparam>
/// <param name="this">The object to parse the JSON string into.</param>
/// <param name="json">The JSON string to parse.</param>
/// <param name="typeResolver">A class to help resolving dynamic or unknown types.</param>
public static void LoadFromJson <T>(this T @this, string json, JsonTypeResolver typeResolver)
{
int start = 0;
LoadFromJson(@this, json, ref start, typeResolver ?? JsonTypeResolver.FromAssemblyMappings <T>());
}
