function Login(){

    var name = $("#txt_loginname").val();
    var pwd = $("#txt_pwd").val();
    
    if(name == '') {
        $("#login_msg").html("请输入用户名");
        return;      
    }
    
    if(pwd == '') {
        $("#login_msg").html("请输入密码");
        return;      
    }

    try
    {
    $.ajax({
        url: '/ws/UserService.asmx/Login',
            data: '{loginName:"' + name + '",password:"' + pwd +'"}',
            type: 'post',
            dataType: 'json',
            contentType: 'application/json; charset=utf8',
            cache: false,
            success: function(data) {
                if (data.d == '1') {                     
                    ShowLogined();
                }
                else if(data.d == '0'){
                    $("#login_msg").html("用户名或密码错误");
                } 
                else{
                    ToLoginPage();
                }
                
            },
            error: function(xhr) {
                alert(xhr.responseText);
            }
        });
        }
        catch(e){
        //alert(e);
        }
    
}

function ToRegPage(){
    window.location.href="http://passport.cnblogs.com/register.aspx";
}

function ShowLogin(){
           var str = "<div id='login_block'>用户名：<input id='txt_loginname' type='text' class='login_input'/>"+
           " 密码：<input id='txt_pwd' type='password' class='login_input'/>"+
           " <input id='btn_login' type='button' value='登录' onclick='Login()'/>"+
           " <input id='btn_reg' type='button' value='注册' onclick='ToRegPage()'/><span id='login_msg' style='color:red'></span></div>";
            if(!document.getElementById("user_block"))
             {
                alert('<div id="user_block"></div>不存在');
             }
             else
             {
                $("#user_block").html(str);
             }
}

function ToLoginPage(){
    window.location.href="http://passport.cnblogs.com/login.aspx?fail=1&ReturnUrl=";
}


function ShowLogined(){    
      $.ajax({
        url: '/ws/UserService.asmx/GetDisplayName',
        data: '{}',
        type: 'post',
        dataType: 'json',
        contentType: 'application/json; charset=utf8',
        cache: false,
        success: function(data) {      
            if (data.d) { 
               ShowLoginedInfo(data.d);              
            }
            else{
                document.write("<span style='color:red'>登录失败</span>");
            }
        },
        error: function(xhr) {
            if(xht.responseText != '')
            {
                alert(xhr.responseText);
            }
            
        }        
    });  
}


function Logout(){
    $.ajax({
        url: '/ws/UserService.asmx/Logout',
        data: '{}',
        type: 'post',
        dataType: 'json',
        contentType: 'application/json; charset=utf8',
        success: function(data) {      
            ShowLogin();
        },
        error: function(xhr) {
            alert(xhr.responseText);
        }
    }); 

}


function ShowLoginedInfo(displayName)
{    
     var str = "<div id='logined_block'> 欢迎您！<a href='http://home.cnblogs.com' class='link_logined'>"+displayName+"</a>"+
     " · <a href='#' class='link_logined' onclick='Logout();return false;'>退出</a></div>";
    if(!document.getElementById("user_block"))
     {
        alert('<div id="user_block"></div>不存在');
     }
     else
     {
        $("#user_block").html(str);
     }
}


ShowLogin();