CookieParameter Class
.NET Framework 4
Binds the value of a client-side HTTP cookie to a parameter object. The parameter can be used in a parameterized query or command to select, filter, or update data.
Namespace:
System.Web.UI.WebControls
Assembly: System.Web (in System.Web.dll)
The CookieParameter type exposes the following members.
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CookieParameter() | Initializes a new unnamed instance of the CookieParameter class. |
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CookieParameter(CookieParameter) | Initializes a new instance of the CookieParameter class with the values of the instance specified by the original parameter. |
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CookieParameter(String, String) | Initializes a new named instance of the CookieParameter class, using the specified string to identify which HTTP cookie to bind to. |
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CookieParameter(String, DbType, String) | Initializes a new instance of the CookieParameter class that has the specified name and database type and that is bound to the specified HTTP cookie. |
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CookieParameter(String, TypeCode, String) | Initializes a new named and strongly typed instance of the CookieParameter class, using the specified string to identify which HTTP cookie to bind to. |
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ConvertEmptyStringToNull | Gets or sets a value indicating whether the value that the Parameter object is bound to should be converted to null if it is String.Empty. (Inherited from Parameter.) |
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CookieName | Gets or sets the name of the HTTP cookie that the parameter binds to. |
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DbType | Gets or sets the database type of the parameter. (Inherited from Parameter.) |
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DefaultValue | Specifies a default value for the parameter, should the value that the parameter is bound to be uninitialized when the Evaluate method is called. (Inherited from Parameter.) |
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Direction | Indicates whether the Parameter object is used to bind a value to a control, or the control can be used to change the value. (Inherited from Parameter.) |
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IsTrackingViewState | Gets a value indicating whether the Parameter object is saving changes to its view state. (Inherited from Parameter.) |
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Name | Gets or sets the name of the parameter. (Inherited from Parameter.) |
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Size | Gets or sets the size of the parameter. (Inherited from Parameter.) |
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Type | Gets or sets the type of the parameter. (Inherited from Parameter.) |
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ViewState | Gets a dictionary of state information that allows you to save and restore the view state of a Parameter object across multiple requests for the same page. (Inherited from Parameter.) |
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Clone | Returns a duplicate of the current CookieParameter instance. (Overrides Parameter.Clone().) |
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Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
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Evaluate | Updates and returns the value of the CookieParameter object. (Overrides Parameter.Evaluate(HttpContext, Control).) |
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Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
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GetDatabaseType | Gets the DbType value that is equivalent to the CLR type of the current Parameter instance. (Inherited from Parameter.) |
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GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
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GetType | Gets the Type of the current instance. (Inherited from Object.) |
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LoadViewState | Restores the data source view's previously saved view state. (Inherited from Parameter.) |
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MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
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OnParameterChanged | Calls the OnParametersChanged method of the ParameterCollection collection that contains the Parameter object. (Inherited from Parameter.) |
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SaveViewState | Saves the changes to the Parameter object's view state since the time the page was posted back to the server. (Inherited from Parameter.) |
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SetDirty | Marks the Parameter object so its state will be recorded in view state. (Inherited from Parameter.) |
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ToString | Converts the value of this instance to its equivalent string representation. (Inherited from Parameter.) |
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TrackViewState | Causes the Parameter object to track changes to its view state so they can be stored in the control's ViewState object and persisted across requests for the same page. (Inherited from Parameter.) |
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ICloneable.Clone | Returns a duplicate of the current Parameter instance. (Inherited from Parameter.) |
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IStateManager.IsTrackingViewState | Infrastructure. Gets a value indicating whether the Parameter object is saving changes to its view state. (Inherited from Parameter.) |
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IStateManager.LoadViewState | Infrastructure. Restores the data source view's previously saved view state. (Inherited from Parameter.) |
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IStateManager.SaveViewState | Infrastructure. Saves the changes to the Parameter object's view state since the time the page was posted back to the server. (Inherited from Parameter.) |
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IStateManager.TrackViewState | Infrastructure. Causes the Parameter object to track changes to its view state so they can be stored in the control's ViewState object and persisted across requests for the same page. (Inherited from Parameter.) |
You can use the CookieParameter class to bind the value of a client-side HTTP cookie passed as part of an HTTP request to a parameter used by ASP.NET data source controls.
The CookieParameter class provides the CookieName property, which identifies the name of the HttpCookie object to bind to, in addition to those inherited from the Parameter class. The CookieParameter class attempts to bind to the named cookie every time the Evaluate method is called.
Important
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Controls that bind data to the parameter might throw an exception if a CookieParameter object is specified, but no corresponding cookie is passed with the HTTP request. Similarly, they might display no data if the cookie is passed with null. Set the DefaultValue property to avoid these situations where appropriate. |
The following code example demonstrates how to use a SqlDataSource control and CookieParameter object bound to an HTTP cookie to display data from the Northwind Traders database in a GridView control.
<%@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"> void Page_Load(Object sender, EventArgs e){ // These cookies might be added by a login form. // They are added here for simplicity. if (!IsPostBack) { Response.Cookies.Add(new HttpCookie("lname", "davolio")); Response.Cookies.Add(new HttpCookie("loginname","ndavolio")); Response.Cookies.Add(new HttpCookie("lastvisit", DateTime.Now.ToString())); } } </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>ASP.NET Example</title> </head> <body> <form id="form1" runat="server"> <asp:SqlDataSource id="SqlDataSource1" runat="server" DataSourceMode="DataSet" ConnectionString="<%$ ConnectionStrings:MyNorthwind%>" SelectCommand = "SELECT OrderID,CustomerID,OrderDate,RequiredDate,ShippedDate FROM Orders WHERE EmployeeID = (SELECT EmployeeID FROM Employees WHERE LastName = @lastname)"> <SelectParameters> <asp:CookieParameter Name="lastname" CookieName="lname" /> </SelectParameters> </asp:SqlDataSource> <asp:GridView id="GridView1" runat="server" AllowSorting="True" DataSourceID="SqlDataSource1"> </asp:GridView> </form> </body> </html>
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
