QueryStringConverter Class

Definition

Namespace:

System.ServiceModel.Dispatcher

Assembly:

System.ServiceModel.Web.dll

This class converts a parameter in a query string to an object of the appropriate type. It can also convert a parameter from an object to its query string representation.

public ref class QueryStringConverter

public class QueryStringConverter

type QueryStringConverter = class

Public Class QueryStringConverter

Inheritance

Object

QueryStringConverter

Derived

System.ServiceModel.Dispatcher.JsonQueryStringConverter

Examples

The following code shows how to use the QueryStringConverter class to convert between a string and a 32-bit integer.

QueryStringConverter converter = new QueryStringConverter();
if (converter.CanConvert(typeof(Int32)))
    converter.ConvertStringToValue("123", typeof(Int32));
int value = 321;
string strValue = converter.ConvertValueToString(value, typeof(Int32));
Console.WriteLine("the value = {0}, the string representation of the value = {1}", value, strValue);

Dim converter As New QueryStringConverter()
If (converter.CanConvert(GetType(Int32))) Then
    converter.ConvertStringToValue("123", GetType(Int32))
End If

Dim value As Integer = 321
Dim strValue As String = converter.ConvertValueToString(value, GetType(Int32))
Console.WriteLine("the value = {0}, the string representation of the value = {1}", value, strValue)

Remarks

Parameters can be specified in a query string within a URL. This class takes those parameters specified in a string and converts them into objects. For example, the following contract is defined.

[ServiceContract]  
interface Calculator  
{  
   [WebGet(UriTemplate="Add?n1={n1}&n2={n2}")]  
   [OperationContract]  
   long Add(long n1, long n2);  
}  

A Windows Communication Foundation (WCF) service implements this interface and exposes it on an endpoint with the WebHttpBehavior at http://localhost:8000/MyCalcService. The Add service operation can be called by sending an HTTP GET to http://localhost:8000/MyCalcService/Add?n1=10&n2=5. The QueryStringConverter receives this URL and converts the two parameters (n1 and n2) specified in the URL into two long objects with the appropriate values.

You can derive a class from QueryStringConverter to control how query string parameters are mapped into a service operation's parameters.

The QueryStringConverter supports the following types by default:

• Byte

• SByte

• Int16

• Int32

• Int64

• UInt16

• UInt32

• UInt64

• Single

• Double

• Char

• Decimal

• Boolean

• String

• DateTime

• TimeSpan

• Guid

• Byte array

• Uri

• Object

• DateTimeOffset

• Enums

• Types that have a TypeConverterAttribute that can convert the type to and from a string representation.

Constructors

QueryStringConverter()

Initializes a new instance of the QueryStringConverter class.

Methods

CanConvert(Type)	Determines whether the specified type can be converted to and from a string representation.
ConvertStringToValue(String, Type)	Converts a query string parameter to the specified type.
ConvertValueToString(Object, Type)	Converts a parameter to a query string representation.
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetType()	Gets the Type of the current instance. (Inherited from Object)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)