//------------------------------------------------------------------------------
// <copyright file="Button.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
namespace System.Web.UI.WebControls {
using System;
using System.Collections;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Drawing.Design;
using System.Web;
using System.Web.UI;
using System.Web.Util;
/// <devdoc>
/// <para>Represents a Windows button control.</para>
/// </devdoc>
[
DataBindingHandler("System.Web.UI.Design.TextDataBindingHandler, " + AssemblyRef.SystemDesign),
DefaultEvent("Click"),
DefaultProperty("Text"),
Designer("System.Web.UI.Design.WebControls.ButtonDesigner, " + AssemblyRef.SystemDesign),
ToolboxData("<{0}:Button runat=\"server\" Text=\"Button\"></{0}:Button>"),
SupportsEventValidation
]
public class Button : WebControl, IButtonControl, IPostBackEventHandler {
private static readonly object EventClick = new object();
private static readonly object EventCommand = new object();
/// <devdoc>
/// <para>Initializes a new instance of the <see cref='System.Web.UI.WebControls.Button'/> class.</para>
/// </devdoc>
public Button() : base(HtmlTextWriterTag.Input) {
}
/// <devdoc>
/// <para>Gets or sets whether pressing the button causes page validation to fire. This defaults to True so that when
/// using validation controls, the validation state of all controls are updated when the button is clicked, both
/// on the client and the server. Setting this to False is useful when defining a cancel or reset button on a page
/// that has validators.</para>
/// </devdoc>
[
DefaultValue(true),
Themeable(false),
WebCategory("Behavior"),
WebSysDescription(SR.Button_CausesValidation),
]
public virtual bool CausesValidation {
get {
object b = ViewState["CausesValidation"];
return((b == null) ? true : (bool)b);
}
set {
ViewState["CausesValidation"] = value;
}
}
/// <devdoc>
/// <para>Gets or sets the command associated with a <see cref='System.Web.UI.WebControls.Button'/> propogated in the <see langword='Command'/> event along with the <see cref='System.Web.UI.WebControls.Button.CommandArgument'/>
/// property.</para>
/// </devdoc>
[
DefaultValue(""),
Themeable(false),
WebCategory("Behavior"),
WebSysDescription(SR.WebControl_CommandName),
]
public string CommandName {
get {
string s = (string)ViewState["CommandName"];
return((s == null) ? String.Empty : s);
}
set {
ViewState["CommandName"] = value;
}
}
/// <devdoc>
/// <para>Gets or sets the property propogated in
/// the <see langword='Command'/> event with the associated <see cref='System.Web.UI.WebControls.Button.CommandName'/>
/// property.</para>
/// </devdoc>
[
Bindable(true),
DefaultValue(""),
Themeable(false),
WebCategory("Behavior"),
WebSysDescription(SR.WebControl_CommandArgument),
]
public string CommandArgument {
get {
string s = (string)ViewState["CommandArgument"];
return((s == null) ? String.Empty : s);
}
set {
ViewState["CommandArgument"] = value;
}
}
/// <devdoc>
/// The script that is executed on a client-side click.
/// </devdoc>
[
DefaultValue(""),
Themeable(false),
WebCategory("Behavior"),
WebSysDescription(SR.Button_OnClientClick),
]
public virtual string OnClientClick {
get {
string s = (string)ViewState["OnClientClick"];
if (s == null) {
return String.Empty;
}
return s;
}
set {
ViewState["OnClientClick"] = value;
}
}
[
DefaultValue(""),
Editor("System.Web.UI.Design.UrlEditor, " + AssemblyRef.SystemDesign, typeof(UITypeEditor)),
Themeable(false),
UrlProperty("*.aspx"),
WebCategory("Behavior"),
WebSysDescription(SR.Button_PostBackUrl),
]
public virtual string PostBackUrl {
get {
string s = (string)ViewState["PostBackUrl"];
return s == null? String.Empty : s;
}
set {
ViewState["PostBackUrl"] = value;
}
}
/// <devdoc>
/// <para>Gets or sets the text caption displayed on the <see cref='System.Web.UI.WebControls.Button'/> .</para>
/// </devdoc>
[
Bindable(true),
Localizable(true),
WebCategory("Appearance"),
DefaultValue(""),
WebSysDescription(SR.Button_Text),
]
public string Text {
get {
string s = (string)ViewState["Text"];
return((s == null) ? String.Empty : s);
}
set {
ViewState["Text"] = value;
}
}
/// <devdoc>
/// Whether the button should use the client's submit mechanism to implement its
/// behavior, or whether it should use the ASP.NET postback mechanism similar
/// to LinkButton. By default, it uses the browser's submit mechanism.
/// </devdoc>
[
DefaultValue(true),
Themeable(false),
WebCategory("Behavior"),
WebSysDescription(SR.Button_UseSubmitBehavior),
]
public virtual bool UseSubmitBehavior {
get {
object b = ViewState["UseSubmitBehavior"];
return ((b == null) ? true : (bool)b);
}
set {
ViewState["UseSubmitBehavior"] = value;
}
}
[
DefaultValue(""),
Themeable(false),
WebCategory("Behavior"),
WebSysDescription(SR.PostBackControl_ValidationGroup),
]
public virtual string ValidationGroup {
get {
string s = (string)ViewState["ValidationGroup"];
return((s == null) ? String.Empty : s);
}
set {
ViewState["ValidationGroup"] = value;
}
}
/// <devdoc>
/// <para>Occurs when the <see cref='System.Web.UI.WebControls.Button'/> is clicked.</para>
/// </devdoc>
[
WebCategory("Action"),
WebSysDescription(SR.Button_OnClick)
]
public event EventHandler Click {
add {
Events.AddHandler(EventClick, value);
}
remove {
Events.RemoveHandler(EventClick, value);
}
}
/// <devdoc>
/// <para>Occurs when the <see cref='System.Web.UI.WebControls.Button'/> is clicked.</para>
/// </devdoc>
[
WebCategory("Action"),
WebSysDescription(SR.Button_OnCommand)
]
public event CommandEventHandler Command {
add {
Events.AddHandler(EventCommand, value);
}
remove {
Events.RemoveHandler(EventCommand, value);
}
}
/// <internalonly/>
/// <devdoc>
/// <para>Adds the attributes of the <see cref='System.Web.UI.WebControls.Button'/> control to the output stream for rendering
/// on the client.</para>
/// </devdoc>
protected override void AddAttributesToRender(HtmlTextWriter writer) {
bool submitButton = UseSubmitBehavior;
// Make sure we are in a form tag with runat=server.
if (Page != null) {
Page.VerifyRenderingInServerForm(this);
}
if (submitButton) {
writer.AddAttribute(HtmlTextWriterAttribute.Type, "submit");
}
else {
writer.AddAttribute(HtmlTextWriterAttribute.Type, "button");
}
PostBackOptions options = GetPostBackOptions();
string uniqueID = UniqueID;
// Don't render Name on a button if __doPostBack is posting back to a different control
// because Page will register this control as requiring post back notification even though
// it's not the target of the postback. If the TargetControl isn't this control, this control's
// RaisePostBackEvent should never get called. See VSWhidbey 477095.
if (uniqueID != null && (options == null || options.TargetControl == this)) {
writer.AddAttribute(HtmlTextWriterAttribute.Name, uniqueID);
}
writer.AddAttribute(HtmlTextWriterAttribute.Value, Text);
//
bool effectiveEnabled = IsEnabled;
string onClick = String.Empty;
if (effectiveEnabled) {
// Need to merge the onclick attribute with the OnClientClick
// VSWhidbey 111791: Defensively add a ';' in case it is
// missing in user customized onClick value above.
onClick = Util.EnsureEndWithSemiColon(OnClientClick);
if (HasAttributes) {
string userOnClick = Attributes["onclick"];
if (userOnClick != null) {
onClick += Util.EnsureEndWithSemiColon(userOnClick);
Attributes.Remove("onclick");
}
}
if (Page != null) {
string reference = Page.ClientScript.GetPostBackEventReference(options, false);
if (reference != null) {
onClick = Util.MergeScript(onClick, reference);
}
}
}
if (Page != null) {
Page.ClientScript.RegisterForEventValidation(options);
}
if (onClick.Length > 0) {
writer.AddAttribute(HtmlTextWriterAttribute.Onclick, onClick);
if (EnableLegacyRendering) {
writer.AddAttribute("language", "javascript", false);
}
}
if (Enabled && !effectiveEnabled && SupportsDisabledAttribute) {
// We need to do the cascade effect on the server, because the browser
// only renders as disabled, but doesn't disable the functionality.
writer.AddAttribute(HtmlTextWriterAttribute.Disabled, "disabled");
}
base.AddAttributesToRender(writer);
}
protected virtual PostBackOptions GetPostBackOptions() {
PostBackOptions options = new PostBackOptions(this, String.Empty);
options.ClientSubmit = false;
if (Page != null) {
if (CausesValidation && Page.GetValidators(ValidationGroup).Count > 0) {
options.PerformValidation = true;
options.ValidationGroup = ValidationGroup;
}
if (!String.IsNullOrEmpty(PostBackUrl)) {
options.ActionUrl = HttpUtility.UrlPathEncode(ResolveClientUrl(PostBackUrl));
}
options.ClientSubmit = !UseSubmitBehavior;
}
return options;
}
/// <devdoc>
/// <para>Raises the <see langword='Click '/>event of a <see cref='System.Web.UI.WebControls.Button'/>
/// .</para>
/// </devdoc>
protected virtual void OnClick(EventArgs e) {
EventHandler handler = (EventHandler)Events[EventClick];
if (handler != null) handler(this,e);
}
/// <devdoc>
/// <para>Raises the <see langword='Command '/>event of a <see cref='System.Web.UI.WebControls.Button'/>
/// .</para>
/// </devdoc>
protected virtual void OnCommand(CommandEventArgs e) {
CommandEventHandler handler = (CommandEventHandler)Events[EventCommand];
if (handler != null)
handler(this,e);
// Command events are bubbled up the control heirarchy
RaiseBubbleEvent(this, e);
}
protected internal override void OnPreRender(EventArgs e) {
base.OnPreRender(e);
// VSWhidbey 489577
if (Page != null && IsEnabled) {
if ((CausesValidation && Page.GetValidators(ValidationGroup).Count > 0) ||
!String.IsNullOrEmpty(PostBackUrl)) {
Page.RegisterWebFormsScript();
}
else if (!UseSubmitBehavior) {
Page.RegisterPostBackScript();
}
}
}
/// <internalonly/>
/// <devdoc>
/// </devdoc>
protected internal override void RenderContents(HtmlTextWriter writer) {
// Do not render the children of a button since it does not
// make sense to have children of an <input> tag.
}
/// <internalonly/>
/// <devdoc>
/// <para>Raises events for the <see cref='System.Web.UI.WebControls.Button'/>
/// control on post back.</para>
/// </devdoc>
void IPostBackEventHandler.RaisePostBackEvent(string eventArgument) {
RaisePostBackEvent(eventArgument);
}
/// <internalonly/>
/// <devdoc>
/// <para>Raises events for the <see cref='System.Web.UI.WebControls.Button'/>
/// control on post back.</para>
/// </devdoc>
protected virtual void RaisePostBackEvent(string eventArgument) {
ValidateEvent(this.UniqueID, eventArgument);
if (CausesValidation) {
Page.Validate(ValidationGroup);
}
OnClick(EventArgs.Empty);
OnCommand(new CommandEventArgs(CommandName, CommandArgument));
}
}
}