QueryStringParameter Constructor (String, TypeCode, String)
Initializes a new named and strongly typed instance of the QueryStringParameter class, using the specified string to identify which query-string field to bind to.
Assembly: System.Web (in System.Web.dll)
Parameters
- name
-
Type:
System.String
The name of the parameter.
- type
-
Type:
System.TypeCode
The type that the parameter represents. The default is Object.
- queryStringField
-
Type:
System.String
The name of the query-string field that the parameter object is bound to. The default is an empty string ("").
A QueryStringParameter object that is created by using the QueryStringParameter constructor is initialized with the specified parameter name, the parameter type, and a string that identifies the query-string field that the parameter binds to. The Direction and ConvertEmptyStringToNull properties are initialized with default values.
The following example shows how to create a QueryStringParameter object by using the QueryStringParameter constructor and add it to an AccessDataSource control's FilterParameters collection. A GridView control displays data if the employee and country query-string fields are passed with the request and if they have valid values.
<%@ Page language="C#"%> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> private void Page_Load(object sender, System.EventArgs e) { QueryStringParameter countryFilter = new QueryStringParameter("country", TypeCode.String, "country"); MyAccessDataSource.FilterParameters.Add(countryFilter); } </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>ASP.NET Example</title> </head> <body> <form id="Form1" method="post" runat="server"> <!-- Use a Query String with country=USA --> <asp:gridview id ="GridView1" runat="server" datasourceid="MyAccessDataSource" /> <!-- Security Note: The AccessDataSource uses a QueryStringParameter, Security Note: which does not perform validation of input from the client. Security Note: To validate the value of the QueryStringParameter, handle the Selecting event. --> <asp:accessdatasource id="MyAccessDataSource" runat="server" datafile="Northwind.mdb" selectcommand="SELECT EmployeeID, LastName, Address, PostalCode, Country FROM Employees" filterexpression="Country = '{0}'"> </asp:accessdatasource> </form> </body> </html>
Available since 2.0