HTML表单OnSubmit报错ReferenceError: sendMsg未定义，求助解决

你的代码存在多个语法和概念错误，直接导致函数无法被识别，以下是逐个修复点：

1. 脚本标签类型错误 #

你写的<script type="javascript/text">是错误格式，正确的MIME类型为text/javascript，现代浏览器可直接省略type属性：

<script>
// 函数代码
</script>

2. JavaScript无public关键字 #

JS声明函数不需要public修饰符，直接删除即可：

function sendMsg() {
  // 函数逻辑
}

3. 语法错误修复 #

• JS中不等于运算符是!==，而非<>，将telNo <> ""改为telNo !== ""
• 第三个if语句缺少闭合括号，且逻辑判断错误：原本的正则匹配逻辑写反了，应该判断邮箱不匹配正则时触发错误，修正为：

  if (email === "" || !regEmail.test(email))
  

4. const变量无法重新赋值 #

你用const send = true;声明变量后又尝试send = false;，这会触发赋值错误，将const改为let：

let send = true;

5. 正则表达式全局标志问题 #

全局匹配的正则（带g标志）使用test方法会有状态残留，导致多次验证结果异常，去掉所有正则的g标志：

var regEmail=/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/; 
var regPhone=/^\d{10}$/;                       
var regName = /\d+$/; 

6. 表单提交返回值 #

函数末尾需要添加return send;，这样验证不通过时会阻止表单默认提交行为，确保验证逻辑生效。

修复后的完整代码 #

<!DOCTYPE html >
<html lang="en">
<head>
    <!-- email from javascript -->
    <script>
        // import {GenericEmail} from '../../js/Email/ElasticEmail.js';
        
        function sendMsg() 
        {
            var regEmail=/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/; 
            var regPhone=/^\d{10}$/;                       
            var regName = /\d+$/; 
            
            let send = true;
            
            const name = document.forms.ContactForm.ContactName.value;
            const telNo = document.forms.ContactForm.ContactTel.value;
            const email = document.forms.ContactForm.ContactEmail.value;
            const msg = document.forms.ContactForm.ContactMsg.value;
            
            if (name === "" || regName.test(name))
            {
                send = false;
                document.forms.ContactForm.ContactName.placeholder = "Name is required";
            }
            
            if (telNo !== "" && !regPhone.test(telNo))
            {
                send = false;
                document.forms.ContactForm.ContactTel.placeholder = "Valid phone number required";
            }
            
            if (email === "" || !regEmail.test(email))
            {
                send = false;
                document.forms.ContactForm.ContactEmail.placeholder = "Email address is required";
            }
            
            if (msg.trim().length === 0)
            {
                send = false;
                document.forms.ContactForm.ContactMsg.placeholder = "Say something...";
            }
            
            if (send)
            {
                const sender = new GenericEmail();
                const result = sender.SendMail("YourNuttyLady", name, telNo, email, msg);
                if (result === "ok")
                {
                    alert("Message was sent !");
                }
            }
            return send;
        }
    </script>
</head>
<body>
    <div class="page-wrapper">
        <!-- Contact Us -->
        <form class="submission-form" name="ContactForm" onsubmit="return sendMsg()" method="POST">
            <input type="text" id="first-name" name="ContactName" placeholder="Enter your name"> </br>
            <input type="tel" id="phone" name="ContactTel" placeholder="Enter your phone number">   </br>
            <input type="email" id ="email" name="ContactEmail" placeholder="Enter your email"></br>
            <textarea id="message" name="ContactMsg" placeholder="Enter your message"></textarea>
            <input type="submit" id="sendBtn" value="send" name="ContactSend">
        </form>
    </div>
</body>
</html>

内容的提问来源于stack exchange，提问作者AlexC