Ecshop Ajax refreshing Login

<! -- Start text --> <! -- {If $ user_info} --> <Div class = "lef_tit_bj"> member logon </div> <Div class = "left_conn_bj"> <Table width = "100%" border =" 0 "cellspacing =" 0 "cellpadding =" 0 "> <tr> <TD Height =" 50 "align =" center "valign =" Middle "> <label> <strong> hello {$ user_info.username} </strong> </label> </TD> </tr> <TD Height = "30" align = "center" valign = "Middle "> <strong> welcome to our store </strong> </TD> </tr> <TD Height =" 40 "align =" center "valign =" B Ottom "> <label> <a href =" user. php? Act = logout ">  </a> & nbsp; <a href =" user. PHP ">  </a> </label> </TD> </tr> </table> </div> <! -- {Else} --> <Div class = "lef_tit_bj"> member logon </div> <Div class = "left_conn_bj"> <Form ID = "ecs_loginform" name = "ecs_loginform" method = "Post" Action = "javascript: signin () "> <Table width =" 100% "border =" 0 "cellspacing =" 0 "cellpadding =" 0 "> <tr> <TD Height =" 50 "align =" right" valign = "Middle"> User Name: </TD> <TD Height = "50" align = "Left" valign = "Middle"> <label> <input type = "text" name = "username" class =" yonhu_input "Style = "Height: 15px; "/> </label> </TD> </tr> <TD Height =" 30 "align =" right "valign =" Middle "> password & nbsp; code: </TD> <TD Height = "30" align = "Left" valign = "Middle"> <input type = "password" name = "password" class = "yonhu_input" Style = "height: 15px; "/> </TD> </tr> <TD Height =" 40 "colspan =" 2 "align =" center "valign =" bottom "> <label> <input type = "image" name = "imagefield" src = "images/denglu_bann.jpg"/> & nbsp; <a HRE F = "user. php? Act = register ">  </a> </label> </TD> </tr> </table> </form> </div> <! -- {/If} --> {literal} <SCRIPT type = "text/JavaScript"> function signin () {var FRM = document. forms ['ecs _ loginform']; If (FRM) {var username = FRM. elements ['username']. value; var Password = FRM. elements ['Password']. value; var CAPTCHA = ''; If (FRM. elements ['captcha ']) {CAPTCHA = FRM. elements ['captcha ']. value;} If (username. length = 0 | password. length = 0) {/literal} alert ("{$ Lang. empty_username_password }");{ Literal} return;} else {Ajax. Call ('user. php? Act = signin ', 'username =' + username + '& Password =' + encodeuricomponent (password) + '& CAPTCHA =' + CAPTCHA, signinresponse, "Post ", "text") ;}} else {alert ('template error! ') ;}} Function signinresponse (result) {var username = document. forms ['ecs _ loginform']. elements ['username']. value; var mzone = document. getelementbyidx_xx_x ("ecs_memberzone"); var res = result. parsejson (); If (res. error> 0){alert(res.content1_if(res.html) {mzone. innerhtml = res.html; document. forms ['ecs _ loginform']. elements ['username']. value = username ;}} else {If (mzone) {mzone. innerhtml = res. content; evalscript (res. ucdata); // alert (res. ucdata);} else {window. location. reload () }}</script >{/ literal}