求一个找jpg图片的详细代码

Question

如何找出一大段html代码中的图片。对于 正则表达式完全不懂，希望高手能给写个完整的方法。假设 目标html代码为 string a； 需要找出的图片格式为.jpg, .gif, .png.希望高手给出详细代码，谢谢了。

Answer 1

这个得看你HTML代码的内容才能写出相应的正则表达式。
然后再得用这个表达去匹配

Answer 2

MatchCollection mc = Regex.Match(html,@"(?is)(?<=<img src=(['""])?)(https?)?[^""]+(?:jpg|png|gif)(?=\1)");
foreach(Match m in mc)
{}

Answer 3

 /// <summary>
        /// 图片选择的处理
        /// bmp格式
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnScan_Click(object sender, EventArgs e)
        {
            OpenFileDialog op = new OpenFileDialog();
            //op.InitialDirectory = @"\..\LMS\Src\LMS\Image";
op.Filter = "图像文件 (*.bmp;*.jpg)|*.bmp;*.jpg";
            if (op.ShowDialog() == DialogResult.OK)
            {
                //System.IO.Path.GetFileName(op.FileName);//得到文件名
                //System.IO.Path.GetDirectoryName(op.FileName);//得到路径
                //bool isTrue = false;
                try
                {
                    using (System.Drawing.Image img = System.Drawing.Image.FromFile(op.FileName))
                    {
                        img.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Jpeg);
                    }
                }
                catch
                {
                    lblMsg.Text = cm.GetMessage("E00066");
                    lblMsg.ForeColor = Color.Red;
                    return;
                }
                string m = op.FileName.Substring(op.FileName.LastIndexOf("."));
                if (m == ".bmp" || m == ".jpg")
                {
                    txtImgPath.Text = Path.GetDirectoryName(op.FileName) + op.FileName.Substring(op.FileName.LastIndexOf("\\"));
                    //txtImgPath.Text = System.Windows.Forms.Application.StartupPath+"\\Image"+ op.FileName.Substring(op.FileName.LastIndexOf("\\"));
                    //ptbImage.Image = Image.FromFile(txtImgPath.Text);
//ADD BY LIU                     /********** ADD By chenshihu 20101116 ********/
                    //如果改文件为“只读”，则修改它的属性
                    bool isFileReadOnly = false;
                    if (File.GetAttributes(txtImgPath.Text).ToString().IndexOf("ReadOnly") != -1)
                    {
                        isFileReadOnly = true;
                        File.SetAttributes(txtImgPath.Text, FileAttributes.Normal);
                    }
                    /*********************************************/ FileStream files = new FileStream(txtImgPath.Text, FileMode.Open);
byte[] imgbyte = new byte[files.Length];
files.Read(imgbyte, 0, imgbyte.Length);
files.Close();                    //ADD By chenshihu 20101119， 操作完成后，将文件的属性还原为“只读”
                    if (isFileReadOnly)
                    {
                        File.SetAttributes(txtImgPath.Text, FileAttributes.ReadOnly);
                    } MemoryStream ms = new MemoryStream(imgbyte, false);
ms.Read(imgbyte, 0, imgbyte.Length);
try
{
ptbImage.Image = Image.FromStream(ms, false);
}
catch { ptbImage.Image = null; }
                }
                else
                {
                    if (ComLibrary.getAsk(cm.GetMessage("E00016"), "?", "提示", true))
                    {
                        btnScan.PerformClick();
                    }
                }
            }
        }

Answer 4

 /// <summary>
        /// 图片选择的处理
        /// bmp格式
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnScan_Click(object sender, EventArgs e)
        {
            OpenFileDialog op = new OpenFileDialog();
            //op.InitialDirectory = @"\..\LMS\Src\LMS\Image";
op.Filter = "图像文件 (*.bmp;*.jpg)|*.bmp;*.jpg";
            if (op.ShowDialog() == DialogResult.OK)
            {
                //System.IO.Path.GetFileName(op.FileName);//得到文件名
                //System.IO.Path.GetDirectoryName(op.FileName);//得到路径
                //bool isTrue = false;
                try
                {
                    using (System.Drawing.Image img = System.Drawing.Image.FromFile(op.FileName))
                    {
                        img.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Jpeg);
                    }
                }
                catch
                {
                    lblMsg.Text = cm.GetMessage("E00066");
                    lblMsg.ForeColor = Color.Red;
                    return;
                }
                string m = op.FileName.Substring(op.FileName.LastIndexOf("."));
                if (m == ".bmp" || m == ".jpg")
                {
                    txtImgPath.Text = Path.GetDirectoryName(op.FileName) + op.FileName.Substring(op.FileName.LastIndexOf("\\"));
                    //txtImgPath.Text = System.Windows.Forms.Application.StartupPath+"\\Image"+ op.FileName.Substring(op.FileName.LastIndexOf("\\"));
                    //ptbImage.Image = Image.FromFile(txtImgPath.Text);
//ADD BY LIU                     /********** ADD By chenshihu 20101116 ********/
                    //如果改文件为“只读”，则修改它的属性
                    bool isFileReadOnly = false;
                    if (File.GetAttributes(txtImgPath.Text).ToString().IndexOf("ReadOnly") != -1)
                    {
                        isFileReadOnly = true;
                        File.SetAttributes(txtImgPath.Text, FileAttributes.Normal);
                    }
                    /*********************************************/ FileStream files = new FileStream(txtImgPath.Text, FileMode.Open);
byte[] imgbyte = new byte[files.Length];
files.Read(imgbyte, 0, imgbyte.Length);
files.Close();                    //ADD By chenshihu 20101119， 操作完成后，将文件的属性还原为“只读”
                    if (isFileReadOnly)
                    {
                        File.SetAttributes(txtImgPath.Text, FileAttributes.ReadOnly);
                    } MemoryStream ms = new MemoryStream(imgbyte, false);
ms.Read(imgbyte, 0, imgbyte.Length);
try
{
ptbImage.Image = Image.FromStream(ms, false);
}
catch { ptbImage.Image = null; }
                }
                else
                {
                    if (ComLibrary.getAsk(cm.GetMessage("E00016"), "?", "提示", true))
                    {
                        btnScan.PerformClick();
                    }
                }
            }
        }

Answer 5

基本上 格式是这样的 <IMG border=0 alt=1.JPG src=\"http://10.66.44.100:30001/FCKeditor/1001003/zhudj20110114081811.JPG\" width=600></P>
<img src="img/2.jpg" />

Answer 6

这个正则表达式取不到值。 另外 应该是=regex.matches 不是 match