js 异步请求
Posted 墨初
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<p id="check"> <label>验证码：</label> <input class="vid" id="ValidateCode" name="ValidateCode" type="text" value="" onblur="checkValidateCode()"/> <img id="checkcodeimg" src="<%=path %>/image.jsp" style="margin-left:10px;" width="74px" height="28px" onclick="this.src=‘<%=path %>/image.jsp?date=‘+new Date();"/> <span id="codeSpan"></span> </p>
image.jsp
1 <%@ page contentType="image/jpeg" import="java.awt.*, java.awt.image.*,java.util.*,javax.imageio.*"%> 2 <%!Color getRandColor(int fc, int bc) { 3 Random random = new Random(); 4 if (fc > 255) 5 fc = 255; 6 if (bc > 255) 7 bc = 255; 8 int r = fc + random.nextInt(bc - fc); 9 int g = fc + random.nextInt(bc - fc); 10 int b = fc + random.nextInt(bc - fc); 11 return new Color(r, g, b); 12 }%> 13 <% 14 out.clear();//????resin???????tomacat?????? 15 out = pageContext.pushBody(); 16 response.setHeader("Pragma", "No-cache"); 17 response.setHeader("Cache-Control", "no-cache"); 18 response.setDateHeader("Expires", 0); 19 20 int width = 60, height = 20; 21 BufferedImage image = new BufferedImage(width, height, 22 BufferedImage.TYPE_INT_RGB); 23 24 Graphics g = image.getGraphics(); 25 Random random = new Random(); 26 27 g.setColor(getRandColor(200, 250)); 28 g.fillRect(0, 0, width, height); 29 30 g.setFont(new Font("Times New Roman", Font.PLAIN, 18)); 31 32 g.setColor(getRandColor(160, 200)); 33 for (int i = 0; i < 155; i++) { 34 int x = random.nextInt(width); 35 int y = random.nextInt(height); 36 int xl = random.nextInt(12); 37 int yl = random.nextInt(12); 38 g.drawLine(x, y, x + xl, y + yl); 39 } 40 41 String sRand = ""; 42 for (int i = 0; i < 4; i++) { 43 String rand = String.valueOf(random.nextInt(10)); 44 sRand += rand; 45 46 g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110))); 47 g.drawString(rand, 13 * i + 6, 16); 48 } 49 // ??????SESSION 50 session.setAttribute("rand", sRand); 51 g.dispose(); 52 53 ImageIO.write(image, "JPEG", response.getOutputStream()); 54 %>
实现jsp
1 var xmlHttpRequest; 2 //XmlHttpRequest对象 3 function createXmlHttpRequest(){ 4 if(window.ActiveXObject){ //如果是IE 5 return new ActiveXObject("Microsoft.XMLHTTP"); 6 }else if(window.XMLHttpRequest){ //非IE浏览器 7 return new XMLHttpRequest(); 8 } 9 } 10 function checkValidateCode(){ 11 code = document.getElementById("ValidateCode").value.trim(); 12 var url = "user_validateCodeCheck.do?validateCode="+code; 13 xmlHttpRequest = createXmlHttpRequest(); 14 xmlHttpRequest.onreadystatechange = HuiDiaoFun; 15 xmlHttpRequest.open("post",url,true); 16 xmlHttpRequest.send(null); 17 } 18 19 //回调函数 20 function HuiDiaoFun(){ 21 if(xmlHttpRequest.readyState == 4 && xmlHttpRequest.status == 200){ 22 var resp = xmlHttpRequest.responseText; 23 if (resp == "error") { 24 document.getElementById("codeSpan").innerhtml = "验证码错误！"; 25 document.getElementById("codeSpan").style.color = "#FF0000"; 26 }else if(resp == "ok"){ 27 document.getElementById("codeSpan").innerHTML = ""; 28 } 29 } 30 }
1 public class UserAction extends BaseAction{ 2 3 4 private String validateCode; 5 6 7 public void validateCodeCheck(){ 8 String code = (String)getHttpSession().getAttribute("rand"); 9 System.out.println(code); 10 if(StringUtils.isNoneEmpty(validateCode) && validateCode.equals(code)){ 11 ResponseUtil.writeUTF(getHttpResponse(), "ok"); 12 }else{ 13 ResponseUtil.writeUTF(getHttpResponse(), "error"); 14 } 15 } 16 17 } 18 19 20 21 22 import java.io.IOException; 23 import java.io.UnsupportedEncodingException; 24 import java.util.Enumeration; 25 import java.util.HashMap; 26 import java.util.List; 27 import java.util.Map; 28 29 import javax.servlet.ServletContext; 30 import javax.servlet.http.HttpServletRequest; 31 import javax.servlet.http.HttpServletResponse; 32 import javax.servlet.http.HttpSession; 33 import javax.servlet.jsp.PageContext; 34 35 import org.apache.struts2.ServletActionContext; 36 import org.springframework.web.context.support.WebApplicationContextUtils; 37 38 import com.opensymphony.xwork2.ActionSupport; 39 40 41 42 /** 43 * action基类，提供共用方法 44 * 45 * 46 */ 47 public class BaseAction extends ActionSupport { 48 49 public UnitService baseUnitService; 50 public RoleService baseRoleService; 51 public ConfigService baseConfigService; 52 public ChannelService baseChannelService; 53 public InfoService baseInfoService; 54 public int pageSize=10; 55 public int currPage=1; 56 public int totalCount=0; 57 public String pageStr; 58 public String pageFuncId; 59 public String showMessage; 60 public String forwardUrl=""; 61 public int forwardSeconds=0; 62 public String getForwardUrl() { 63 return forwardUrl; 64 } 65 public void setForwardUrl(String forwardUrl) { 66 this.forwardUrl = forwardUrl; 67 } 68 public int getForwardSeconds() { 69 return forwardSeconds; 70 } 71 public void setForwardSeconds(int forwardSeconds) { 72 this.forwardSeconds = forwardSeconds; 73 } 74 public int getPageSize() { 75 return pageSize; 76 } 77 public void setPageSize(int pageSize) { 78 this.pageSize = pageSize; 79 } 80 public int getCurrPage() { 81 return currPage; 82 } 83 public void setCurrPage(int currPage) { 84 this.currPage = currPage; 85 } 86 public HttpSession getHttpSession(){ 87 return ServletActionContext.getRequest().getSession(); 88 } 89 public HttpServletRequest getHttpRequest(){ 90 return ServletActionContext.getRequest(); 91 } 92 public HttpServletResponse getHttpResponse(){ 93 return ServletActionContext.getResponse(); 94 } 95 public PageContext getPageContext(){ 96 return ServletActionContext.getPageContext(); 97 } 98 public ServletContext getServletContext(){ 99 return ServletActionContext.getServletContext(); 100 } 101 public Map<String, Object> getApplication(){ 102 return ServletActionContext.getContext().getApplication(); 103 } 104 public String getBasePath(){ 105 String path = getHttpRequest().getContextPath(); 106 String basePath = getHttpRequest().getScheme()+"://"+getHttpRequest().getServerName()+":"+getHttpRequest().getServerPort()+path+"/"; 107 return basePath; 108 } 109 110 111 /** 112 * 获取配置 113 * @return 114 */ 115 public Map<String, Object> getConfig(){ 116 if (getApplication().get("config")!=null) { 117 return (Map<String, Object>)getApplication().get("config"); 118 }else { 119 //重新生成 120 return setConfig(); 121 } 122 } 123 /** 124 * 获取配置值 125 * @return 126 */ 127 public String getConfigVal(String name){ 128 Map<String, Object> config=getConfig(); 129 if (config!=null && config.get(name)!=null) { 130 return config.get(name).toString(); 131 } 132 return ""; 133 } 134 /** 135 * 设置配置 136 * @return 137 */ 138 public Map<String, Object> setConfig(){ 139 baseConfigService = (ConfigService) getBean("configService"); 140 List<Config> configList=baseConfigService.find(); 141 Map<String, Object> config=new HashMap<String, Object>(); 142 if (configList!=null && configList.size()>0) { 143 for (int i = 0; i < configList.size(); i++) { 144 config.put(configList.get(i).getCode(), configList.get(i).getConfigvalue()); 145 } 146 } 147 getApplication().put("config", config); 148 return config; 149 } 150 public void write(String content,String charset){ 151 getHttpResponse().setCharacterEncoding(charset); 152 getHttpResponse().setContentType("text/html;charset="+charset); 153 try { 154 getHttpResponse().getWriter().print(content); 155 } catch (IOException e) { 156 e.printStackTrace(); 157 } 158 } 159 /** 160 * 判断是否为admin登录 161 */ 162 public boolean isAdminLogin(){ 163 return "admin".equals(getLoginName()); 164 } 165 /** 166 * 判断是否为站点总管理员 167 */ 168 public boolean isSiteAdmin(){ 169 if (getHttpSession().getAttribute("siteAdmin")!=null) { 170 return (Boolean)getHttpSession().getAttribute("siteAdmin"); 171 } 172 return false; 173 } 174 /** 175 * 获取当前管理站点 176 * @return 177 */ 178 public Site getManageSite(){ 179 if (getHttpSession().getAttribute("manageSite")!=null) { 180 //获取当前管理站点 181 return (Site)getHttpSession().getAttribute("manageSite"); 182 } 183 return null; 184 } 185 /** 186 * 获取session中的当前登录用户名 187 * @return 188 */ 189 public String getLoginName(){ 190 if (getLoginAdmin()!=null) { 191 return getLoginAdmin().getLoginname(); 192 } 193 return ""; 194 } 195 /** 196 * 获取session中的当前登录用户 197 * @return 198 */ 199 public Users getLoginAdmin(){ 200 if (getHttpSession().getAttribute("loginAdmin")!=null) { 201 return (Users)getHttpSession().getAttribute("loginAdmin"); 202 } 203 return null; 204 } 205 /** 206 * 获取session中的当前登录会员 207 * @return 208 */ 209 public Member getLoginMember(){ 210 if (getHttpSession().getAttribute("loginMember")!=null) { 211 return (Member)getHttpSession().getAttribute("loginMember"); 212 } 213 return null; 214 } 215 /** 216 * 获取session中的当前登录会员组 217 * @return 218 */ 219 public Membergroup getLoginMembergroup(){ 220 if (getHttpSession().getAttribute("loginMembergroup")!=null) { 221 return (Membergroup)getHttpSession().getAttribute("loginMembergroup"); 222 } 223 return null; 224 } 225 /** 226 * 获取session中的当前会员登录用户名 227 * @return 228 */ 229 public String getLoginMemberName(){ 230 if (getLoginMember()!=null) { 231 return getLoginMember().getLoginname(); 232 } 233 return ""; 234 } 235 236 /** 237 * 获取登录用户所属单位 238 * @return 239 */ 240 public List<Unit> getLoginUnits(){ 241 //先判断session是否存在 242 HttpSession session=getHttpSession(); 243 if (session.getAttribute("loginUnits")!=null) { 244 return (List<Unit>)session.getAttribute("loginUnits"); 245 }else { 246 //不存在则重新提取 247 baseUnitService = (UnitService) getBean("unitService"); 248 List<Unit> list = baseUnitService.findByUser(getLoginAdmin().getId()); 249 session.setAttribute("loginUnits", list); 250 return list; 251 } 252 } 253 /** 254 * 获取登录用户所属单位组成的sql语句 255 * 例:‘‘,‘‘,‘‘ 256 * @return 257 */ 258 public String getLoginUnitIdsSql(){ 259 List<Unit> list=getLoginUnits(); 260 StringBuilder sb=new StringBuilder(); 261 if (list!=null && list.size()>0) { 262 for (int i = 0; i < list.size(); i++) { 263 if (i>0) { 264 sb.append(","); 265 } 266 sb.append("‘"+list.get(i).getId()+"‘"); 267 } 268 } 269 return sb.toString(); 270 } 271 /** 272 * 获取登录用户所属角色 273 * @return 274 */ 275 public List<Roles> getLoginRoles(){ 276 //先判断session是否存在 277 HttpSession session=getHttpSession(); 278 if (session.getAttribute("loginRoles")!=null) { 279 return (List<Roles>)session.getAttribute("loginRoles"); 280 }else { 281 //不存在则重新提取 282 baseRoleService = (RoleService) getBean("roleService"); 283 List<Roles> list = baseRoleService.findByUser(getLoginAdmin().getId()); 284 session.setAttribute("loginRoles", list); 285 return list; 286 } 287 } 288 /** 289 * 获取登录用户所属角色组成的sql语句 290 * 例:‘‘,‘‘,‘‘ 291 * @return 292 */ 293 public String getLoginRoleIdsSql(){ 294 List<Roles> list=getLoginRoles(); 295 StringBuilder sb=new StringBuilder(); 296 if (list!=null && list.size()>0) { 297 for (int i = 0; i < list.size(); i++) { 298 if (i>0) { 299 sb.append(","); 300 } 301 sb.append("‘"+list.get(i).getId()+"‘"); 302 } 303 } 304 return sb.toString(); 305 } 306 /** 307 * 返回到通用信息提示页面 308 * @param msg 309 * @param url 310 * @param seconds 311 * @return 312 */ 313 public String showMessage(String showMessage,String forwardUrl,int forwardSeconds){ 314 this.showMessage=showMessage; 315 this.forwardUrl=forwardUrl; 316 this.forwardSeconds=forwardSeconds; 317 return "showMessage"; 318 } 319 /** 320 * 设置静态化参数 321 * @param data 322 * @throws UnsupportedEncodingException 323 */ 324 public void setData(Map<String,Object> data,Site site) throws UnsupportedEncodingException{ 325 //传递site参数 326 data.put("site", site); 327 data.put("contextPath", getContextPath()); 328 data.put("contextPathNo", getContextPathNo()); 329 data.put("request_remoteAddr", getHttpRequest().getRemoteAddr()); 330 //获取参数并放入data 331 Enumeration<String> paramNames=getHttpRequest().getParameterNames(); 332 if (paramNames!=null && paramNames.hasMoreElements()) { 333 String name; 334 while (paramNames.hasMoreElements()) { 335 name=paramNames.nextElement(); 336 if (name!=null && 337 !name.equals("site") && 338 !name.equals("contextPath")&& 339 !name.equals("currChannelid")&& 340 !name.equals("currInfoid")) { 341 if(name.equals("key")){ 342 String key = new String(getHttpRequest().getParameter(name).getBytes(),"UTF-8"); 343 data.put(name, key); 344 }else{ 345 data.put(name, getHttpRequest().getParameter(name)); 346 } 347 } 348 } 349 } 350 //如果有currChannelid参数则传递currChannel对象 351 if (getHttpRequest().getParameter("currChannelid")!=null && getHttpRequest().getParameter("currChannelid").trim().length()>0) { 352 baseChannelService = (ChannelService) getBean("channelService"); 353 data.put("currChannel",baseChannelService.findById(getHttpRequest().getParameter("currChannelid"))); 354 } 355 //如果有currInfoid参数则传递currInfo对象 356 if (getHttpRequest().getParameter("currInfoid")!=null && getHttpRequest().getParameter("currInfoid").trim().length()>0) { 357 baseInfoService = (InfoService) getBean("infoService"); 358 data.put("currInfo",baseInfoService.findById(getHttpRequest().getParameter("currInfoid"))); 359 } 360 //获取seesion中存放的变量 361 Enumeration<String> sessionNames=getHttpSession().getAttributeNames(); 362 if (sessionNames!=null && sessionNames.hasMoreElements()) { 363 String name; 364 while (sessionNames.hasMoreElements()) { 365 name=sessionNames.nextElement(); 366 if (name!=null) { 367 //session变量名称改为session_变量名，避免重名 368 data.put("session_"+name, getHttpSession().getAttribute(name)); 369 } 370 } 371 } 372 } 373 public String getContextPath(){ 374 return getHttpRequest().getContextPath()+"/"; 375 } 376 public String getContextPathNo(){ 377 return getHttpRequest().getContextPath()+"/"; 378 } 379 public String getPageStr() { 380 return pageStr; 381 } 382 public void setPageStr(String pageStr) { 383 this.pageStr = pageStr; 384 } 385 public int getTotalCount() { 386 return totalCount; 387 } 388 public void setTotalCount(int totalCount) { 389 this.totalCount = totalCount; 390 } 391 public String getPageFuncId() { 392 return pageFuncId; 393 } 394 public void setPageFuncId(String pageFuncId) { 395 this.pageFuncId = pageFuncId; 396 } 397 public UnitService getBaseUnitService() { 398 return baseUnitService; 399 } 400 public void setBaseUnitService(UnitService baseUnitService) { 401 this.baseUnitService = baseUnitService; 402 } 403 public RoleService getBaseRoleService() { 404 return baseRoleService; 405 } 406 public 以上是关于js 异步请求的主要内容，如果未能解决你的问题，请参考以下文章