JSP登录问题求救 急 急 在线等
我现在做了一个登录的界面，界面有一个输入ID和密码的文本框，还有一个下来菜单。
当我输入一个ID的时候，管理员给用户ID分配的功能（角色）能够在下拉菜单中显示出来。改如何实现呢。下面是我写的一个下拉菜单，但是SQL语句中的条件“C_Usr_Id”不知道改如何得到，谢谢大家
<select size= "1 " name= "C_Roles_Name " style= "width:133 ">
<%
ConnDB2Imp conndb = new ConnDB2Imp();//连接DB
String sql = "select a.C_Usr_ID,b.C_Role_ID,c.C_Roles_Name from sys_usr a,sys_role_usr b,sys_roles c where a.C_Usr_ID=b.C_Usr_ID and c.C_Roles_ID=b.C_Role_ID and a.C_Usr_ID= ' "+ C_Usr_Id + " ' ";
ResultSet rs = conndb.returnSelectRs(sql);
try{
while(rs.next())
{
String Role_Name=rs.getString( "C_Roles_Name ");
String Role_ID=rs.getString( "C_Role_ID ");
String Usr_ID = rs.getString( "C_Usr_ID ");
out.println( " <option value= ' " + Usr_ID + " '> " + Role_Name + " </option> ");
}
}catch(Exception e){e.printStackTrace();}
finally{conndb.closeRs();conndb.closeStmt();conndb.closeConn();} %>
</select>
[解决办法]
页面代码:
<form name= "frm1 ">
<table>
<tr> <td>
<input type= "text " id= "ID " name= "ID " onchange= "return check() "/>
</td> </tr>
<tr> <td>
<select name= "role ">
<option value= "-1 "> select role </option>
</select>
</td> </tr>
</table>
</form>
<script>
var xmlHttp1;
try {
xmlHttp1 = new ActiveXObject( "Msxml2.xmlHttp ");
} catch (e) {
try {
xmlHttp1 = new ActiveXObject( "Microsoft.xmlHttp ");
} catch (e2) {
xmlHttp1 = false;
}
}
function check() {
var ID = document.getElementById( "ID ").value;
if ((ID == null) || (ID.match(/^\s*$/)))return;
// Build the URL to connect to
var url = "/test/checkValue?ID= " + escape(ID);
// Open a connection to the server
xmlHttp1.open( "post ",url, true);
// Setup a function for the server to run when it 's done
xmlHttp1.onreadystatechange = updatePage1;
// Send the request
xmlHttp1.send(null);
}
function updatePage1() {
if (xmlHttp1.readyState == 4 && xmlHttp1.status==200) {
var xmldom = xmlHttp1.responseXML;
var rootElement = xmldom.documentElement;
var roles = rootElement.childNodes;
var select_role = document.frm1.role;
select_role.options[0] = new Option( 'select role ', '-1 ');
for(var i=0;i <roles.length;i++){
select_role.options[i+1]=new Option(roles[i].text,roles[i].text);
}
}
}
</script>
servlet代码:
protected void doGet(HttpServletRequest arg0, HttpServletResponse arg1)
throws ServletException, IOException {
PrintWriter out = arg1.getWriter();
arg1.setContentType( "text/xml;charset=gb2312 ");
out.println( " <roles> ");
out.println( " <role> aa </role> ");
out.println( " <role> bb </role> ");
out.println( " </roles> ");
}
protected void doPost(HttpServletRequest arg0, HttpServletResponse arg1)
throws ServletException, IOException {
this.doGet(arg0, arg1);
}
测试成功,至于连接数据库的话,那应该没有什么问题吧
