Question

我想在JSP页面的MySQL表中显示一个blob（图像），我的代码如下：

  <%
    Blob image = null;
    Connection con = null;
    Statement stmt = null;
    ResultSet rs = null;
    byte[ ] imgData = null ; 

    String DRIVER= "com.mysql.jdbc.Driver";
    String databaseName = "imd";
    String connectionUrl = "jdbc:mysql://127.0.0.1:3306/" + databaseName;
    String DB_USER = "root";
    String DB_PASSWD = "root";

    try{
    Class.forName(DRIVER);
    con = DriverManager.getConnection(connectionUrl,DB_USER,DB_PASSWD);
    stmt = con.createStatement();
    rs = stmt.executeQuery("select SiteKey from imd_user_sitekey where userName = 'lili'");
    if (rs.next()) {
       image = rs.getBlob(1);
       imgData = image.getBytes(1,(int)image.length());
    } else {
        out.println("Display Blob Example");
        out.println("image not found for given id>");
        return;
    }
    response.setContentType("image/gif");
    OutputStream out = response.getOutputStream();
    out.write(imgData);
    out.flush();
    oout.close();
    }catch (Exception e) {
        out.println("Unable To Display image");
        out.println("Image Display Error=" + e.getMessage());
        return;
        } finally {
        try {
        rs.close();
        stmt.close();
        con.close();
        } catch (SQLException e) {
        e.printStackTrace();
        }
        }

  %> 

 <h1>Hello, <%= message %>, Please enter your password!</h1>
 <br/>
    <html:form action="sitekey">
         <bean:message key="label.password"/>
         <html:password property="password"></html:password>             
        <html:submit/>
    </html:form>

图片可以成功显示，但其他内容低于＆lt; %%＆gt;我的JSP页面中的代码没有显示出来，整个页面就像一张图片一样。有人可以帮我解决这个问题吗？非常感谢你！

Answer 1

这是因为你设置了response.setContentType("image/gif");。要在页面中显示HTMl，JSP页面内容类型必须为response.setContentType("text/html");

Answer 2

这段代码可以帮助你....这是我的show_image.jsp

<%
String id="1250";
session.setAttribute("num", id);
%>
  <body>
  <image src="display.jsp" border="0" height="200px" width="200px"/>


      <h1>Hello, Please enter your password!</h1>
     <br/>
     <html:form action="sitekey">
     <bean:message key="label.password"/>
     <html:password property="password"></html:password>             
    <html:submit/>
    </html:form>
 </body>

这里我通过dispaly.jsp文件外部引用图像

 <% Blob image = null;
 String no=(String)session.getAttribute("num"); 
 byte[ ] imgData = null ;
 Statement stmt = null;
 ResultSet rs = null;
 try {
     Class.forName("com.mysql.jdbc.Driver");
     Connection con = (Connection);      DriverManager.getConnection("jdbc:mysql://localhost:3306/test","root","");
     stmt = con.createStatement();
     rs = stmt.executeQuery("select photo from file1 where id = '"+no+"'");
     if (rs.next()) {
     image = rs.getBlob(1);
     imgData = image.getBytes(1,(int)image.length());
     } else {
            out.println("Display Blob Example");
            out.println("image not found for given id");
            return;
            }
      // display the image
   response.setContentType("image/gif");
   OutputStream o = response.getOutputStream();
   o.write(imgData);
   o.flush();
   o.close();
    } catch (Exception e) {
                           out.println("Unable To Display image");
                           out.println("Image Display Error=" + e.getMessage());
                           return;
                          } finally {
                                    try {
                                         rs.close();
                                         stmt.close();
                                        } catch (SQLException e) {
                                                                 System.out.println(e);
                                                                 e.printStackTrace();
                                                                 }
                         }
       %>

使用JSP从Mysql表中显示Blob（Image）的问题

2 个答案: