Question

我的vue组件是这样的：

<template>
    <span class="rating">
        ...
    </span>
</template>
<script>
    export default {
        props: {
            'star': null
        }, 
        ...
    }
</script>

如果组件正在运行，我想在浏览器中禁用按钮。因此用户无法返回上一页

我该怎么做？

Answer 1

每当网址更改时运行此代码。它将抵消用户的后退行动

window.history.forward(1)

Answer 2

尝试此脚本，方法是在HTML文件中添加创建Vue实例的位置

//Entire api.php file
<?php
// helper function, which outputs error messages in JSON format
// so that the iPhone app can read them
// the function just takes in a dictionary with one key "error" and 
// encodes it in JSON, then prints it out and then exits the program
function errorJson($msg){
print json_encode(array('error'=>$msg));
exit();
}

// register API
function register($user, $pass) {

//check if username exists in the database (inside the "login" table)
$login = query("SELECT username FROM login WHERE username='%s' limit 1", $user);

if (count($login['result'])>0) {

    //the username exists, return error to the iPhone app
    errorJson('Username already exists');
}

//try to insert a new row in the "login" table with the given username and password
$result = query("INSERT INTO login(username, pass) VALUES('%s','%s')", $user, $pass);

if (!$result['error']) {
    //registration is susccessfull, try to also directly login the new user
    login($user, $pass);
} else {
    //for some database reason the registration is unsuccessfull
    errorJson('Registration failed');
}

}

//login API
function login($user, $pass) {

// try to match a row in the "login" table for the given username and password
$result = query("SELECT IdUser, username FROM login WHERE username='%s' AND pass='%s' limit 1", $user, $pass);

if (count($result['result'])>0) {
    // a row was found in the database for username/pass combination
    // save a simple flag in the user session, so the server remembers that the user is authorized
    $_SESSION['IdUser'] = $result['result'][0]['IdUser'];
    
    // print out the JSON of the user data to the iPhone app; it looks like this:
    // {IdUser:1, username: "Name"}
    print json_encode($result);
} else {
    // no matching username/password was found in the login table
    errorJson('Authorization failed');
}

}

//upload API
function upload($id, $photoData, $title) {

// index.php passes as first parameter to this function $_SESSION['IdUser']
// $_SESSION['IdUser'] should contain the user id, if the user has already been authorized
// remember? you store the user id there in the login function
if (!$id) errorJson('Authorization required');

// check if there was no error during the file upload
if ($photoData['error']==0) {

    // insert the details about the photo to the "photos" table

    //1. change ok
    $result = query("INSERT INTO photos(IdUser,title) VALUES('%d','%s')", $id, $title);
    if (!$result['error']) {

        // fetch the active connection to the database (it's initialized automatically in lib.php)
        global $link;
     
        // get the last automatically generated ID in the photos table
        $IdPhoto = mysqli_insert_id($link);
     
        // move the temporarily stored file to a convenient location
        // your photo is automatically saved by PHP in a temp folder
        // you need to move it over yourself to your own "upload" folder
        if (move_uploaded_file($photoData['tmp_name'], "upload/".$IdPhoto.".jpg")) {

            // file moved, all good, generate thumbnail
            thumb("upload/".$IdPhoto.".jpg", 180);
            
            //just print out confirmation to the iPhone app
            print json_encode(array('successful'=>1));
        } else {
            //print out an error message to the iPhone app
            errorJson('Upload on server problem');
        };

    } else {
        errorJson('Hmm...Upload database problem.'.$result['error']);
    }
} else {
    errorJson('Upload malfunction');
}
}

//logout API
function logout() {

// by saving an empty array to $_SESSION you are
// effectively destroying all the user session data
// ie. the server won't "remember" anymore anything about
// the current user
$_SESSION = array();

// and to make double-sure, there's also a built-in function 
// which wipes out the user session
session_destroy();
}

//stream API
//
// there are 2 ways to use the function:
// 1) don't pass any parameters - then the function will fetch all photos from the database
// 2) pass a photo id as a parameter - then the function will fetch the data of the requested photo
//
// Q: what "$IdPhoto=0" means? A: It's the PHP way to say "first param of the function is $IdPhoto, 
// if there's no param sent to the function - initialize $IdPhoto with a default value of 0"
function stream($IdPhoto=0) {

if ($IdPhoto==0) {

    // load the last 50 photos from the "photos" table, also join the "login" so that you can fetch the 
    // usernames of the photos' authors
    $result = query("SELECT IdPhoto, title, l.IdUser, username FROM photos p JOIN login l ON (l.IdUser = p.IdUser) ORDER BY IdPhoto DESC LIMIT 50");

} else {
    //do the same as above, but just for the photo with the given id
    $result = query("SELECT IdPhoto, title, l.IdUser, username FROM photos p JOIN login l ON (l.IdUser = p.IdUser) WHERE p.IdPhoto='%d' LIMIT 1", $IdPhoto);
}

if (!$result['error']) {
    // if no error occured, print out the JSON data of the 
    // fetched photo data
    print json_encode($result);
} else {
    //there was an error, print out to the iPhone app
    errorJson('Photo stream is broken');
}
}

如何使用vue组件禁用浏览器上的后退按钮？

2 个答案: