D:/Projects/Anthem/Anthem/PlaceHolder.cs

using System;
using System.ComponentModel;
using System.Drawing;
using System.Web.UI;
using ASP = System.Web.UI.WebControls;

namespace Anthem
{
    [ToolboxBitmap(typeof(ASP.PlaceHolder))]
    public class PlaceHolder : ASP.PlaceHolder, IUpdatableControl, ICallBackContainerControl
    {
        #region Unique Anthem control code

        private const string parentTagName = "span";
        protected override void Render(HtmlTextWriter writer)
        {
#if !V2
            bool DesignMode = this.Context == null;
#endif
            if (EnableCallBack && AddCallBacks)
                Anthem.Manager.AddCallBacks(this,
                    EnabledDuringCallBack,
                    TextDuringCallBack,
                    PreCallBackFunction,
                    PostCallBackFunction,
                    CallBackCancelledFunction);

            if (!DesignMode)
            {
                Anthem.Manager.WriteBeginControlMarker(writer, parentTagName, this);
            }
            if (Visible)
            {
                base.Render(writer);
            }
            if (!DesignMode)
            {
                Anthem.Manager.WriteEndControlMarker(writer, parentTagName, this);
            }
        }

        #endregion

        #region ICallBackControl implementation

        [Category("Anthem")]
        [DefaultValue("")]
        [Description("The javascript function to call on the client if the callback is cancelled.")]
        public virtual string CallBackCancelledFunction
        {
            get
            {
                string text = (string)ViewState["CallBackCancelledFunction"];
                if (text == null)
                    return string.Empty;
                else
                    return text;
            }
            set
            {
                ViewState["CallBackCancelledFunction"] = value;
            }
        }

        [Category("Anthem")]
        [DefaultValue(true)]
        [Description("True if this control uses callbacks instead of postbacks to post data to the server.")]
        public virtual bool EnableCallBack
        {
            get
            {
                object obj = this.ViewState["EnableCallBack"];
                if (obj == null)
                    return true;
                else
                    return (bool)obj;
            }
            set
            {
                ViewState["EnableCallBack"] = value;
            }
        }

        [Category("Anthem")]
        [DefaultValue(true)]
        [Description("True if this control is enabled on the client during callbacks.")]
        public virtual bool EnabledDuringCallBack
        {
            get
            {
                object obj = this.ViewState["EnabledDuringCallBack"];
                if (obj == null)
                    return true;
                else
                    return (bool)obj;
            }
            set
            {
                ViewState["EnabledDuringCallBack"] = value;
            }
        }


        [Category("Anthem")]
        [DefaultValue("")]
        [Description("The javascript function to call on the client after the callback response is received.")]
        public virtual string PostCallBackFunction
        {
            get
            {
                string text = (string)this.ViewState["PostCallBackFunction"];
                if (text == null)
                {
                    return string.Empty;
                }
                return text;
            }
            set
            {
                ViewState["PostCallBackFunction"] = value;
            }
        }

        [Category("Anthem")]
        [DefaultValue("")]
        [Description("The javascript function to call on the client before the callback is made.")]
        public virtual string PreCallBackFunction
        {
            get
            {
                string text = (string)this.ViewState["PreCallBackFunction"];
                if (text == null)
                {
                    return string.Empty;
                }
                return text;
            }
            set
            {
                ViewState["PreCallBackFunction"] = value;
            }
        }

        [Category("Anthem")]
        [DefaultValue("")]
        [Description("The text to display during the callback.")]
        public virtual string TextDuringCallBack
        {
            get
            {
                string text = (string)this.ViewState["TextDuringCallBack"];
                if (text == null)
                {
                    return string.Empty;
                }
                return text;
            }
            set
            {
                ViewState["TextDuringCallBack"] = value;
            }
        }

        #endregion

        #region ICallBackContainerControl implementation

        [Category("Anthem")]
        [DefaultValue(true)]
        [Description("True if this control should convert child control postbacks into callbacks.")]
        public virtual bool AddCallBacks
        {
            get
            {
                object obj = this.ViewState["AddCallBacks"];
                if (obj == null)
                    return true;
                else
                    return (bool)obj;
            }
            set
            {
                ViewState["AddCallBacks"] = value;
            }
        }

        #endregion

        #region IUpdatableControl implementation

        [Category("Anthem")]
        [DefaultValue(false)]
        [Description("True if this control should be updated after each callback.")]
        public virtual bool AutoUpdateAfterCallBack
        {
            get
            {
                object obj = this.ViewState["AutoUpdateAfterCallBack"];
                if (obj == null)
                    return false;
                else
                    return (bool)obj;
            }
            set
            {
                if (value) UpdateAfterCallBack = true;
                ViewState["AutoUpdateAfterCallBack"] = value;
            }
        }

        private bool _updateAfterCallBack = false;

        [Browsable(false)]
        [DefaultValue(false)]
        public virtual bool UpdateAfterCallBack
        {
            get { return _updateAfterCallBack; }
            set { _updateAfterCallBack = value; }
        }

        #endregion

        #region Common Anthem control code

        protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);
            Anthem.Manager.Register(this);
        }

#if V2
        public override void RenderControl(HtmlTextWriter writer)
        {
            base.Visible = true;
            base.RenderControl(writer);
        }
#endif

        public override bool Visible
        {
            get
            {
#if !V2
                bool DesignMode = this.Context == null;
#endif
                return Anthem.Manager.GetControlVisible(this, ViewState, DesignMode);
            }
            set { Anthem.Manager.SetControlVisible(ViewState, value); }
        }

        #endregion
    }
}

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