在Javascript验证后提交表单

Question

我希望将表单提交到使用后验证后PHP调用的文件.该形式给出如下:reg.phpJavaScriptHTML

HTML表格:

<form method="post">
   <input type="text" id="username" name="username"></input>        
   <button type="button" onclick="val()">Sign Up</button>
</form>

JavaScript验证

以下是JavaScript验证码:

function val(){

    var uname = document.getElementById('username').value;
    if(!uname){
        document.getElementById("error").innerHTML = "Enter a username";
        return false;
    }
    else{
        // I want to submit form if this else statement executes.
    }


}

Answer 1

只需添加action="reg.php"在<form>和返回VAL()函数onclick,也使type="submit"形成的提交,如:

<form method="post" action="reg.php">
   <input type="text" id="username" name="username"></input>        
   <button type="submit" onclick="return val()">Sign Up</button>
</form>

并且只需添加return true;在else这样的:

function val(){

    var uname = document.getElementById('username').value;
    if(!uname){
        document.getElementById("error").innerHTML = "Enter a username";
        return false;
    }
    else{
        return true;
    }
}