binaryimage.cs

数据库保存2进制图片D

using System;
using System.Collections.Specialized;
using System.Collections.Generic;
using System.Text;
using System.Drawing;
using System.Drawing.Design;
using System.Drawing.Imaging;
using System.IO;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Web;
using System.Web.UI;
using System.Web.UI.Design;
using System.Web.UI.WebControls;

[assembly: WebResource("myControls.WeblRes.BinaryImage_Desgin.png", "image/x-png")]
[assembly: WebResource("myControls.WeblRes.BinaryImage_Erro.png", "image/x-png")]
namespace myControls
{
    [ToolboxData("<{0}:BinaryImage runat=server></{0}:BinaryImage>"), Designer(typeof(BinaryImageDesigner)), Description("")]
    public class BinaryImage : WebControl
    {
        private byte[] m_Binary;
        private bool m_FixIsDefault;

        public BinaryImage()
        {

        }


        #region 相关属性

        #region 公开属性

        [Browsable(false), Description("图片二进制数据")]
        public byte[] Binary
        {
            get { return m_Binary; }
            set { m_Binary = value; }
        }

        [DefaultValue(false), Description("是否以固定图片为首选项：true优先显示固定图片，false则优先显示二进制图片")]
        public bool FixIsDefault
        {
            get { return m_FixIsDefault; }
            set { m_FixIsDefault = value; }
        }

        [DefaultValue(""), Description("设置固定图片地址"), Editor(typeof(ImageUrlEditor), typeof(UITypeEditor))]
        public virtual string FixImageSrc
        {
            get
            {
                object obj = this.ViewState["FixImageSrc"];
                return (obj == null) ? string.Empty : obj.ToString();
            }
            set
            {
                this.ViewState["FixImageSrc"] = value;
            }
        }

        [DefaultValue(0), Category("Layout"), Description("图片对齐方式")]
        public virtual System.Web.UI.WebControls.ImageAlign ImageAlign
        {
            get
            {
                object obj1 = this.ViewState["ImageAlign"];
                if (obj1 != null)
                {
                    return (System.Web.UI.WebControls.ImageAlign)obj1;
                }
                return System.Web.UI.WebControls.ImageAlign.NotSet;
            }
            set
            {
                if ((value < System.Web.UI.WebControls.ImageAlign.NotSet) || (value > System.Web.UI.WebControls.ImageAlign.TextTop))
                {
                    throw new ArgumentOutOfRangeException("value");
                }
                this.ViewState["ImageAlign"] = value;
            }
        }

        #endregion

        private bool IsImageShowing
        {
            get
            {
                bool flag1;
                try
                {
                    flag1 = (this.Page.Request["BinaryImage"] != null) && (this.Page.Request["BinaryImage"] == this.ClientID);
                }
                catch
                {
                    flag1 = false;
                }
                return flag1;
            }
        }

        private bool IsNothing
        {
            get
            {
                if ((this.Binary != null) && (this.Binary.Length != 0) || !string.IsNullOrEmpty(this.FixImageSrc))
                {
                    return false;
                }
                return true;
            }
        }

        protected virtual string ImageUrl
        {
            get
            {
                NameValueCollection col = new NameValueCollection();
                col.Add("BinaryImage", this.ClientID);
                return BuildUrlString(col);
            }
        }


        #endregion


        protected override void OnLoad(EventArgs e)
        {
            if (this.IsImageShowing)
            {
                if (!this.IsNothing)
                    this.RenderImage();
            }
            base.OnLoad(e);

        }

        protected override void Render(HtmlTextWriter writer)
        {
            writer.WriteBeginTag("img");
            if (this.TabIndex != 0)
            {
                writer.WriteAttribute("tabindex", this.TabIndex.ToString());
            }
            writer.WriteAttribute("border", "0");

            if (!this.IsNothing)
            {
                writer.WriteAttribute("src", this.ImageUrl);
                writer.WriteAttribute("Title", this.ToolTip);
            }
            else
            {
                writer.WriteAttribute("src", this.Page.ClientScript.GetWebResourceUrl(typeof(BinaryImage), "myControls.WeblRes.BinaryImage_Erro.png"));
                writer.WriteAttribute("Title", "控件未曾初始化");
            }

            writer.WriteAttribute("id", this.ClientID + "_image");

            if (!string.IsNullOrEmpty(this.CssClass))
                writer.WriteAttribute("Class", this.CssClass);
            if (!this.Width.IsEmpty)
                writer.WriteAttribute("Width", this.Width.ToString());
            if (!this.Height.IsEmpty)
                writer.WriteAttribute("Height", this.Height.ToString());
            #region 对齐方式
            System.Web.UI.WebControls.ImageAlign align1 = this.ImageAlign;
            if (align1 != System.Web.UI.WebControls.ImageAlign.NotSet)
            {
                string text2;
                switch (align1)
                {
                    case System.Web.UI.WebControls.ImageAlign.Left:
                        {
                            text2 = "left";
                            break;
                        }
                    case System.Web.UI.WebControls.ImageAlign.Right:
                        {
                            text2 = "right";
                            break;
                        }
                    case System.Web.UI.WebControls.ImageAlign.Baseline:
                        {
                            text2 = "baseline";
                            break;
                        }
                    case System.Web.UI.WebControls.ImageAlign.Top:
                        {
                            text2 = "top";
                            break;
                        }
                    case System.Web.UI.WebControls.ImageAlign.Middle:
                        {
                            text2 = "middle";
                            break;
                        }
                    case System.Web.UI.WebControls.ImageAlign.Bottom:
                        {
                            text2 = "bottom";
                            break;
                        }
                    case System.Web.UI.WebControls.ImageAlign.AbsBottom:
                        {
                            text2 = "absbottom";
                            break;
                        }
                    case System.Web.UI.WebControls.ImageAlign.AbsMiddle:
                        {
                            text2 = "absmiddle";
                            break;
                        }
                    default:
                        {
                            text2 = "texttop";
                            break;
                        }
                }
                writer.AddAttribute(HtmlTextWriterAttribute.Align, text2);
            }
            #endregion

            writer.Write('>');
            
        }



        private void RenderImage()
        {
            byte[] byte1;
            if (this.FixIsDefault)
            {
                byte1 = (string.IsNullOrEmpty(this.FixImageSrc)) ? this.Binary : GetFromFile(this.Page.Server.MapPath(this.FixImageSrc));
            }
            else
            {
                byte1 = ((this.Binary != null) && (this.Binary.Length != 0)) ? this.Binary : GetFromFile(this.Page.Server.MapPath(this.FixImageSrc));
            }
            RenderImage(byte1);
        }

        private string BuildUrlString(NameValueCollection col)
        {
            string currentUrl = Page.Request.Path;
            NameValueCollection urlParams = Page.Request.QueryString;
            int i;
            string tempstr = "";
            if (urlParams == null || urlParams.Count <= 0)
            {
                for (i = 0; i < col.Count; i++)
                {
                    tempstr += String.Concat("&", col.Keys[i], "=", col[i]);
                }
                return String.Concat(currentUrl, "?", tempstr.Substring(1));
            }
            NameValueCollection newCol = new NameValueCollection(urlParams);
            string[] newColKeys = newCol.AllKeys;
            for (i = 0; i < newColKeys.Length; i++)
            {
                newColKeys[i] = newColKeys[i].ToLower();
            }
            for (i = 0; i < col.Count; i++)
            {
                if (Array.IndexOf(newColKeys, col.Keys[i].ToLower()) < 0)
                    newCol.Add(col.Keys[i], col[i]);
                else
                    newCol[col.Keys[i]] = col[i];
            }
            System.Text.StringBuilder sb = new System.Text.StringBuilder();
            for (i = 0; i < newCol.Count; i++)
            {
                sb.Append("&");
                sb.Append(newCol.Keys[i]);
                sb.Append("=");
                sb.Append(newCol[i]);
            }
            return String.Concat(currentUrl, "?", sb.ToString().Substring(1));
        }

        #region 静态方法

        public static byte[] GetFromFile(string path)
        {
            FileInfo info1 = new FileInfo(path);
            FileStream stream1 = info1.OpenRead();
            byte[] buffer1 = new byte[stream1.Length];
            stream1.Read(buffer1, 0, int.Parse(stream1.Length.ToString()));
            return buffer1;
        }

        private static void RenderImage(byte[] byteImg)
        {
            System.Drawing.Image image1 = System.Drawing.Image.FromStream(new MemoryStream(byteImg));

            HttpContext.Current.Response.ClearContent();            
            HttpContext.Current.Response.BinaryWrite(byteImg);
            HttpContext.Current.Response.End();
        }


        #endregion
    }


    [SupportsPreviewControl(true)]
    public class BinaryImageDesigner : ControlDesigner
    {
        public override string GetDesignTimeHtml()
        {
            BinaryImage bImg = (BinaryImage)Component;
            string imgUrl = bImg.Page.ClientScript.GetWebResourceUrl(typeof(BinaryImage), "myControls.WeblRes.BinaryImage_Desgin.png");
            
            string imgWidth = bImg.Width.IsEmpty ? string.Empty : string.Format(" Width='{0}' ",bImg.Width.ToString());
            string imgHeight = bImg.Height.IsEmpty ? string.Empty : string.Format(" Height='{0}' ",bImg.Height.ToString());
            return string.Format("<img border='0' src='{0}'{1}{2} Title='设计模式'>", imgUrl, imgWidth, imgHeight);
        }

    }
}