自制"Captcha"系统 - javascript中的一个小故障,无法启用提交按钮

因此,基本上我正在尝试做的安全措施(和学习过程)是我自己的"Capthca"系统.发生的事情是我有二十个"标签"(为简洁起见,下面只显示一个),每个都有1到20之间的ID.我的javascript随机选择其中一个ID并使该图片显示为安全代码.每个标签都有自己的值,对应于验证码图像的文本.

另外,我最初禁用了提交按钮.

我需要帮助的是在有人输入与HTML标签元素中列出的值匹配的正确值时,弄清楚如何启用提交按钮.

我已经发布了用户输入值和ID的值,即使它们匹配,javascript也不会启用提交按钮.

我觉得这是一个非常简单的添加/修复.帮助将非常感谢!!!

HTML代码

Javascript代码

//Picks random image

function pictureSelector() { 
    var number = (Math.round(Math.random() * 20));
        //Prevents zero from being randomly selected which would return an error
        if (number === 0) {
            number = 1;
        };
    console.log(number);

//Set the ID variable to select which image gets enabled

    pictureID = ("#" + number);

//If the siblings have a class of enabled, remove it
    $(pictureID).siblings().removeClass("enabled");
//Add the disabled class to all of the sibling elements so that just the selected ID image is showing 
    $(pictureID).siblings().addClass("disabled");
//Remove the disabled class from the selected ID
    $(pictureID).removeClass("disabled");
//Add the enabled class to the selected ID
    $(pictureID).addClass("enabled");
};

//Calls the pictureSelector function
pictureSelector();

//Gets the value of the picture value
var pictureValue = $(pictureID).attr("value");
console.log(pictureValue);

//Gets the value of the security input box as the user presses the keys and stores it as the variable inputValue
$("#contact-div-captcha-input input").keyup(function(){
    var inputValue = $("#contact-div-captcha-input input").val();
    console.log(inputValue);
});

console.log($("#contact-div-captcha-input input").val());

//Checks to see if the two values match
function equalCheck() {
    //If they match, remove the disabled attribute from the submit button
    if ($(pictureValue) == $("#contact-div-captcha-input input").val()) {
        $("#submit").removeAttr("disabled");
    } 
};

equalCheck();

UPDATE

在这里小提琴

更新#2

$("#contact-div-captcha-input input").keyup(function(){
    var inputValue = $("#contact-div-captcha-input input").val();
    console.log(inputValue);
    if (pictureValue === inputValue) {
        $("#inputsubmit").removeAttr("disabled");
    } 
});

所以我得到了99.9%的工作,现在唯一的问题是,如果有人要退格或删除他们输入的正确值,则提交按钮不会再变回禁用状态.有什么指针吗？