我創建了一個ASP.NET/C#應用程序將圖像上傳到MySQL數據庫。該過程執行時沒有任何錯誤,但對於我上傳的任何圖像,我得到的是100x100白色圖像的輸出。我遵循的程序是。從數據庫中存儲和檢索圖像
1)創建了一個數據庫,其中字段picture
和類型Binary(255)
。
2)上傳的圖像作爲cmd.Parameters.Add("@picture", OdbcType.Binary, 255).Value = FileUpload1.FileBytes;
3)上述被插入一個新的記錄,併產生以下類型的有價值的東西做。 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
// ---------------上傳模塊完成----------------- //
1 )創建一個ASPX頁面
<asp:Image ID="img" runat="server" ImageUrl="~/MyImage.ashx" />
2)左ASPX.CS文件,而無需任何代碼
3)增加了一個ASHX文件,
<%@ WebHandler Language="C#" Class="MyImage" %>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
using System.Drawing.Imaging;
public class MyImage : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "image/png";
var data = "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";
var buffer = StringToByteArray(data);
context.Response.OutputStream.Write(buffer, 0, buffer.Length);
}
private byte[] StringToByteArray(string hex)
{
return Enumerable
.Range(0, hex.Length)
.Where(x => x % 2 == 0)
.Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
.ToArray();
}
public bool IsReusable
{
get { return false; }
}
}
通過執行此代碼,任何彩色輸入的輸出中都會顯示一個白色的100x100圖像。我複選了ContentType
並上傳了各種尺寸和格式的各種圖像,但無論我做什麼,我都得到了相同白色圖像的輸出。我的代碼有什麼問題?任何更正?
不是在MySQL的專家,但你創建與255bytes的最大長度列?因此最大圖像大小確實是255字節? – kolin 2012-01-13 11:42:25
MySQL不允許超過255的二進制文件的長度 – 2012-01-13 13:10:25