怎么直接从数据库中判断Image类型字段的记录是否相等
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用二进制比较试试。
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image无法直接比较，他要比较的话，得逐字节比较
实际上你可以提取image的ＭＤ５值作为特征值，然后比较其特征值是否相等
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逐字节比较的例子
- C# code
using System;using System.Data;using System.Data.SqlClient;using System.Configuration;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Web.UI.HtmlControls;using System.Collections;using System.IO;public partial class _Default : System.Web.UI.Page{ protected void Page_Load(object sender, EventArgs e) { byte[] temp1 = getImage("d://1.jpg"); byte[] temp2 = getImage("d://2.jpg"); bool isEqual=true; //判断图片是否相等 if (temp1.Length==temp2.Length) { for (int i = 0; i < temp1.Length; i++) { if (temp1[i] != temp2[i]) { isEqual = false; } } } else { isEqual = false; } if (isEqual) { Response.Write("<script>alert('两图片相等')</script>"); } else { Response.Write("<script>alert('两图片不相等')</script>"); } } /// <summary> /// 按图片路径把图片打成二进制流 /// </summary> /// <param name="path">图片路径</param> /// <returns></returns> public byte[] getImage(string path) { FileStream fs = File.OpenRead(path); MemoryStream ms = new MemoryStream(); int bdata; while ((bdata = fs.ReadByte()) != -1) { ms.WriteByte(((byte)bdata)); } byte[] data = (byte[])ms.ToArray(); fs.Close(); ms.Close(); fs = null; ms = null; return data; }}