Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/UI/WebControls/Label.cs

@@ -0,0 +1,228 @@
+//------------------------------------------------------------------------------
+// <copyright file="Label.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+
+namespace System.Web.UI.WebControls {
+
+    using System;
+    using System.ComponentModel;
+    using System.Web;
+    using System.Web.UI;
+    using System.Web.Util;
+
+
+
+    /// <devdoc>
+    /// <para>Interacts with the parser to build a <see cref='System.Web.UI.WebControls.Label'/> control.</para>
+    /// </devdoc>
+    public class LabelControlBuilder : ControlBuilder {
+
+
+        /// <internalonly/>
+        /// <devdoc>
+        ///    <para>Specifies whether white space literals are allowed.</para>
+        /// </devdoc>
+        public override bool AllowWhitespaceLiterals() {
+            return false;
+        }
+    }
+
+
+
+    /// <devdoc>
+    ///    <para>Constructs a label for displaying text programmatcially on a
+    ///       page.</para>
+    /// </devdoc>
+    [
+    ControlBuilderAttribute(typeof(LabelControlBuilder)),
+    ControlValueProperty("Text"),
+    DataBindingHandler("System.Web.UI.Design.TextDataBindingHandler, " + AssemblyRef.SystemDesign),
+    DefaultProperty("Text"),
+    ParseChildren(false),
+    Designer("System.Web.UI.Design.WebControls.LabelDesigner, " + AssemblyRef.SystemDesign),
+    ToolboxData("<{0}:Label runat=\"server\" Text=\"Label\"></{0}:Label>")
+    ]
+    public class Label : WebControl, ITextControl {
+
+        private bool _textSetByAddParsedSubObject = false;
+
+        /// <devdoc>
+        /// <para>Initializes a new instance of the <see cref='System.Web.UI.WebControls.Label'/> class and renders
+        ///    it as a SPAN tag.</para>
+        /// </devdoc>
+        public Label() {
+        }
+
+
+        /// <devdoc>
+        /// </devdoc>
+        internal Label(HtmlTextWriterTag tag) : base(tag) {
+        }
+
+
+        /// <devdoc>
+        /// <para>[To be supplied.]</para>
+        /// </devdoc>
+        [
+        DefaultValue(""),
+        IDReferenceProperty(),
+        TypeConverter(typeof(AssociatedControlConverter)),
+        WebCategory("Accessibility"),
+        WebSysDescription(SR.Label_AssociatedControlID),
+        Themeable(false)
+        ]
+        public virtual string AssociatedControlID {
+            get {
+                string s = (string)ViewState["AssociatedControlID"];
+                return (s == null) ? String.Empty : s;
+            }
+            set {
+                ViewState["AssociatedControlID"] = value;
+            }
+        }
+
+        internal bool AssociatedControlInControlTree {
+            get {
+                object o = ViewState["AssociatedControlNotInControlTree"];
+                return (o == null ? true : (bool)o);
+            }
+            set {
+                ViewState["AssociatedControlNotInControlTree"] = value;
+            }
+        }
+
+        public override bool SupportsDisabledAttribute {
+            get {
+                return RenderingCompatibility < VersionUtil.Framework40;
+            }
+        }
+
+        internal override bool RequiresLegacyRendering {
+            get {
+                return true;
+            }
+        }
+
+
+        protected override HtmlTextWriterTag TagKey {
+            get {
+                if (AssociatedControlID.Length != 0) {
+                    return HtmlTextWriterTag.Label;
+                }
+                return base.TagKey;
+            }
+        }
+
+
+        /// <devdoc>
+        /// <para>Gets or sets the text content of the <see cref='System.Web.UI.WebControls.Label'/>
+        /// control.</para>
+        /// </devdoc>
+        [
+        Localizable(true),
+        Bindable(true),
+        WebCategory("Appearance"),
+        DefaultValue(""),
+        WebSysDescription(SR.Label_Text),
+        PersistenceMode(PersistenceMode.InnerDefaultProperty)
+        ]
+        public virtual string Text {
+            get {
+                object o = ViewState["Text"];
+                return((o == null) ? String.Empty : (string)o);
+            }
+            set {
+                if (HasControls()) {
+                    Controls.Clear();
+                }
+                ViewState["Text"] = value;
+            }
+        }
+
+
+        protected override void AddAttributesToRender(HtmlTextWriter writer) {
+            string associatedControlID = AssociatedControlID;
+            if (associatedControlID.Length != 0) {
+                if (AssociatedControlInControlTree) {
+                    Control wc = FindControl(associatedControlID);
+                    if (wc == null) {
+                        // Don't throw in the designer.
+                        if (!DesignMode)
+                            throw new HttpException(SR.GetString(SR.LabelForNotFound, associatedControlID, ID));
+                    }
+                    else {
+                        writer.AddAttribute(HtmlTextWriterAttribute.For, wc.ClientID);
+                    }
+                }
+                else {
+                    writer.AddAttribute(HtmlTextWriterAttribute.For, associatedControlID);
+                }
+            }
+
+            base.AddAttributesToRender(writer);
+        }
+
+
+        /// <internalonly/>
+        /// <devdoc>
+        /// </devdoc>
+        protected override void AddParsedSubObject(object obj) {
+            if (HasControls()) {
+                base.AddParsedSubObject(obj);
+            }
+            else {
+                if (obj is LiteralControl) {
+                    if (_textSetByAddParsedSubObject) {
+                        Text += ((LiteralControl)obj).Text;
+                    }
+                    else {
+                        Text = ((LiteralControl)obj).Text;
+                    }
+                    _textSetByAddParsedSubObject = true;
+                }
+                else {
+                    string currentText = Text;
+                    if (currentText.Length != 0) {
+                        Text = String.Empty;
+                        base.AddParsedSubObject(new LiteralControl(currentText));
+                    }
+                    base.AddParsedSubObject(obj);
+                }
+            }
+        }
+
+
+        /// <internalonly/>
+        /// <devdoc>
+        ///    <para>Load previously saved state.
+        ///       Overridden to synchronize Text property with LiteralContent.</para>
+        /// </devdoc>
+        protected override void LoadViewState(object savedState) {
+            if (savedState != null) {
+                base.LoadViewState(savedState);
+                string s = (string)ViewState["Text"];
+                // Dev10 703061 If Text is set, we want to clear out any child controls, but not dirty viewstate
+                if (s != null && HasControls()) {
+                    Controls.Clear();
+                }
+            }
+        }
+
+
+        /// <internalonly/>
+        /// <devdoc>
+        /// <para>Renders the contents of the <see cref='System.Web.UI.WebControls.Label'/> into the specified writer.</para>
+        /// </devdoc>
+        protected internal override void RenderContents(HtmlTextWriter writer) {
+            if (HasRenderingData()) {
+                base.RenderContents(writer);
+            }
+            else {
+                writer.Write(Text);
+            }
+        }
+    }
+}
+