Provides serialization and deserialization functionality for Microsoft ASP.NET AJAX applications.
Syntax
CSharp
VisualBasic
ManagedCPlusPlus
JSharp
Members
Remarks
Although the JavaScriptSerializer class is used internally by the asynchronous communication layer to serialize and deserialize the data that is passed between the browser and the Web server, you cannot access that instance of the serializer programmatically. However, this class is provided as a public API, so that you can use it directly when you want to work with JavaScript Object Notation (JSON) in managed code.
To serialize an object, invoke the Serialize method. To deserialize a JSON string, invoke the Deserialize<(Of T>)(String) or DeserializeObject(String) methods. To serialize and deserialize types that are not natively supported by JavaScriptSerializer, implement custom converters by using the JavaScriptConverter class, and then register the converters by using the RegisterConverters(IEnumerable<(Of JavaScriptConverter>)) method.
Mapping Between Managed Types and JSON
The following table shows the corresponding mapping between managed types and JSON for the serialization process. These types are natively supported by JavaScriptSerializer. When deserializing from a JSON string to a managed type, the same mapping applies. However, deserialization is asymmetric in its behavior. Not all serializable managed types can be deserialized from JSON.
noteA multidimensional array is serialized as a one-dimensional array; you should use it as a flat array.
Managed type | JSON equivalent |
|---|
String (UTF-8 encoding only). | String. |
Char. | String. |
Single null char (such as, \0 ). | Null. |
Boolean. | Boolean. Represented in JSON as true or false. |
Null values (null object references and Nullable value types). | A null value string. |
DBNull. | A null value string. |
Primitive numeric (or numeric compatible) types: Byte, SByte, Int16, Int32, Int64, UInt16, UInt32, UInt64, Double, Single. The culture invariant string representation is used. | Number. |
DateTime. | Date object. Represented in JSON as "\/Date(number of ticks)\/". The number of ticks is a positive or negative long value that indicates the number of ticks (in milliseconds) that have elapsed since midnight 01 January, 1970 UTC. The maximum supported date value is MaxValue {12/31/9999 11:59:59 PM} and the minimum supported date value is MinValue {1/1/0001 12:00:00 AM}. |
Enumerations. | Integer equivalent of the enumeration value. |
Types that implement IEnumerable, or IEnumerable that are not also implementations of IDictionary or IDictionary. This includes types, such as Array, ArrayList and List. | Array that uses JSON array syntax. |
Types that implement IDictionary or IDictionary. This includes types, such as Dictionary and Hashtable. | JavaScript object that uses JSON dictionary syntax. |
Custom concrete types that have public instance properties with get accessors and/or public instance fields. Note that public write-only properties, public property or public field attributes with ScriptIgnoreAttribute and public indexed properties in these types are ignored. | JavaScript object that uses JSON dictionary syntax. A special metadata property “__type” is included to ensure correct deserialization. |
Guid. | ToString(). |
Uri. | GetComponents(UriComponents, UriFormat). |
Examples
The following example demonstrates how to use the JavaScriptSerializer class to save and restore the state of an object using JSON serialization.
Permissions
- AspNetHostingPermission
for operating in a hosted environment. Demand value: LinkDemand. Associated enumeration: Minimal.
- AspNetHostingPermission
for operating in a hosted environment. Demand value: InheritanceDemand. Associated enumeration: Minimal.
Inheritance Hierarchy
Assembly: System.Web.Extensions (Module: System.Web.Extensions)