将php变量从php函数插入到HTML表单字段中

Question

我编写了一个 php 函数，它根据一组规则生成一个随机密码。 我想在用户单击调用 php 函数的“生成随机密码”按钮（不刷新页面）后将 $randomPassword 变量插入到 HTML 表单字段中。 一旦随机密码出现在表单字段中，用户单击“提交”按钮以更改数据库中的密码。

将 php 变量放入表单字段的最佳方法是什么？ 我已经进行了大量搜索，但无法提出可行的解决方案。

任何有关如何实现这一目标的提示将不胜感激。 谢谢！

*** 编辑 ***

感谢下面的所有反馈，但我今天找到了一个起点，这是表格：

                <form name="passwordform" action="" method="post">
                    <div>
                        <?php
                            if ( $error )
                                echo '<font color="red">'. $message . "<br></font>";
                           else
                               echo $message;
                        ?><br>
                    </div>
                    <div class="wrap-input100 validate-input" data-validate = "password is required">
                        <div class="content">
                            <input class="input100" type="password" id="pass1" name="new_password" placeholder="New Password"</input>
                            <span class="focus-input100-1"></span>
                            <span class="focus-input100-2"></span>
                        </div>
                    </div><br>
                    <div class="wrap-input100 validate-input" data-validate = "password is required">
                        <div class="content">
                            <input class="input100" type="password" id="pass2" name="confirm_new_password" placeholder="Confirm New Password"</input>
                            <span class="focus-input100-1"></span>
                            <span class="focus-input100-2"></span>
                        </div>
                    </div><br>
                    <div class="first">
                        <div class="group1">
                            <input type="checkbox" id="chk">
                            <label id="showhide" class="label">Show Passwords</label>
                        </div>
                    </div>
                    <script src="_js/showhide.js"></script><br>
                    <?php echo $passwordSyntaxMessage . "<br>";
                        if ($reCAPTCHAcheck)
                            echo '<div class="g-recaptcha" data-sitekey=' . $reCAPTCHAsiteKey . '></div><br>';
                    ?>
                    <input class="login100-form-btn" name="insert" type="button" value="Generate Random Password" onClick="randomPassword();" /><br>
                    <div style="float:left; padding-right: 0px">
                        <input class="form-button" style="width: 180px" name="insert" type="submit" value="Set Password" />
                    </div>
                    <div style="float:right; padding-right: 0px">
                        <input class="form-button" style="width: 180px" name="insert" type="reset" value="Reset Form" />
                    </div>
                </form>
                <script type="text/javascript" >
                    function randomPassword() {
                        var pass = <?php echo generateRandomPassword();?>; 
                        passwordform.new_password.value = pass;
                        passwordform.confirm_new_password.value = pass;
                    }
                </script>

如果我单击“生成随机密码”按钮，则 2 个密码字段保持空白。 php 函数 generateRandomPassword() 位于名为 functions.php 的文件中，我知道它可以工作，因为我可以在浏览器中回显结果。

如果我替换该行：

var pass = <?php echo generateRandomPassword();?>;

和：

var pass = "testing 1 2 3";

果然在2个密码字段中插入了短语“testing 1 2 3”！

那么我在调用 php 函数时哪里出错了？

谢谢！

Answer 1

使用以下代码：这可以使用 AJAX 来完成。

索引.html

<form action="" method="">
    <label>Password:</label>
    <input type="text" name="password" id="password" />
    <button type="button" onclick="generate_password();">Generate</button>
    <br /><br />
    <input type="submit" />
</form>
<script>
function generate_password()
{
    var xmlhttp = new XMLHttpRequest();
    xmlhttp.onreadystatechange = function()
    {
        if (this.readyState == 4 && this.status == 200)
        {
            document.getElementById("password").value = this.responseText;
        }
    };
    xmlhttp.open("GET", "action.php", true);
    xmlhttp.send();
}
</script>

动作.php

<?php
if (isset($_GET['generate_password']))
{
    // Add codes your desired PHP function that generate password. I am adding some code that i got from somewhere.
    
    $alpha = "abcdefghijklmnopqrstuvwxyz";
    $alpha_upper = strtoupper($alpha);
    $numeric = "0123456789";
    $special = "!@$#*%";

    // Concatinate all variables into one long string
    $chars = $alpha . $alpha_upper . $numeric . $special;

    // Select password length
    $length = 10;

    // Suffle the value of $chars
    $chars = str_shuffle($chars);

    // Return the length of your new $chars string
    $len = strlen($chars);

    // Create empty variable that will hold your new password
    $pw = '';

    // A simple 'for' statement that will select random characters for the lenth of your password
    for ($i=0;$i<$length;$i++)
        $pw .= substr($chars, rand(0, $len-1), 1); 

    // Store the finished password in a variable, that will shuffle the value created by the 'for' statement
    $pw = str_shuffle($pw);

    // show the password on screen
    echo $pw;
}
?>

Answer 2

请删除 if 条件，因为您没有将任何内容作为查询参数发送，您只是在调用文件名 action.php

            <?php

                // Add codes your desired PHP function that generate password. I am adding some code that i got from somewhere.
                
                $alpha = "abcdefghijklmnopqrstuvwxyz";
                $alpha_upper = strtoupper($alpha);
                $numeric = "0123456789";
                $special = "!@$#*%";

                // Concatinate all variables into one long string
                $chars = $alpha . $alpha_upper . $numeric . $special;

                // Select password length
                $length = 10;

                // Suffle the value of $chars
                $chars = str_shuffle($chars);

                // Return the length of your new $chars string
                $len = strlen($chars);

                // Create empty variable that will hold your new password
                $pw = '';

                // A simple 'for' statement that will select random characters for the lenth of your password
                for ($i=0;$i<$length;$i++)
                    $pw .= substr($chars, rand(0, $len-1), 1); 

                // Store the finished password in a variable, that will shuffle the value created by the 'for' statement
                $pw = str_shuffle($pw);

                // show the password on screen
                echo $pw;

            ?>

现在它将起作用。

Answer 3

您也可以使用 JQuery AJAX

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>

查询

<script>
   function generate_password(){
    $.ajax({
            method: "get",
            data: {generate_password: true},
            url: "action.php",
            success: function(data){
                $("#password").val(data)
            }
        });
    }
</script>