<script type="text/javascript"> 
function changeImage(){ 
  var img = document.getElementById("imgVcode");
  if(img.name == 1){ 
    img.name = 2; 
    img.src = "shop.do";
  }else if(img.name == 2){ 
    img.name = 1; 
    img.src = "shop.do";
  } 
} 
</script>

<td> 
  <img class="yzm_img" id='imgVcode' name="1" src="/UploadFiles/2021-04-02/shop.do">

3.后台action代码


public ActionForward registerImage(ActionMapping mapping, ActionForm form, 
   HttpServletRequest request, HttpServletResponse response)
    throws Exception { 
    //将image创建,返回认证码 
    response.setContentType("image/jpeg"); 
    OutputStream out = response.getOutputStream(); 
    String strEnsure = shopManager.createImageInfo(50,20,out);
    //设置到session中 
    request.getSession().setAttribute("strEnsure", strEnsure);
    return null; 
  } 
  public ActionForward registerImage2(ActionMapping mapping, ActionForm form, 
      HttpServletRequest request, HttpServletResponse response)
      throws Exception { 
    //将image创建,返回认证码 
    response.setContentType("image/jpeg"); 
    OutputStream out = response.getOutputStream(); 
    String strEnsure = shopManager.createImageInfo(50,20,out);
    //设置到session中 
    request.getSession().setAttribute("strEnsure", strEnsure);
    return null; 
} 




希望本文所述对大家的JavaScript程序设计有所帮助。