如何从网页中输入文本，并将Javascript函数应用于文本并将其输出？

大家好，
这次我将尝试更具体一些。
我正在构建一个网页，用户可以在其中写入一些文本，然后在对其应用以下函数后，我希望输出结果，以便用户可以看到。

     function convert1 (word)
{
    var ret = "",
        temp = "",
        tmp = "",
        keep = 0,
        check = 0;

    for (var i = 0;i < 1; i++)
    {
            if (word[0] == "l")
            {
                ret += "l";
            }else if (word[0] == "a" || word[0] == "e" || word[0] == "i" || word[0] == "o" || word[0] == "u")
            {
                ret += "l";
                ret += word[0];
            }else
            {
                ret += "l";
                temp += word[0];
            }
    }
    for (var j = 1; j < word.length; j++)
    {
             if (word[0] == "a" || word[0] == "e" || word[0] == "i" || word[0] == "o" || word[0] == "u")
             {
                if (word[j] == "a" || word[j] == "e" || word[j] == "i" || word[j] == "o" || word[j] == "u" || word[j] == "'" || word[j] == "-")
                {
                    ret += word[j];
                }else
                {
                    keep++;
                    if (keep == 1)
                    {
                        temp = word[j];
                        ret += "l";
                    }else
                    {
                    ret += word[j];
                    }
                }
             }else if (word[0] == "l")
             {
                if (word[j] == "a" || word[j] == "e" || word[j] == "i" || word[j] == "o" || word[j] == "u" || word[j] == "'" || word[j] == "-")
                {
                    ret += word[j];
                }else
                {
                 keep++;
                    if (keep == 1)
                    {
                        temp += word[j];
                        ret += "l";
                    }else 
                    {
                        ret += word[j];
                    }
                }
             }else
             {
                ret += word[j];
             }
    }   
    ret += temp;
    for (var k = 1;k < ret.length; k++){
        if (ret[k] == "a" || ret[k] == "e" || ret[k] == "i" || ret[k] == "o" || ret[k] == "u" || ret[k] == "'" || ret[k] == "-")
        {}else{
            check += 1;
        } 
    }
    if (check > 0)
    {
        ret += "i";
    }
    return ret;
}

---

不起作用，如何使其起作用？

您应该提供自己的功能，但它是这样的：

HTML

---

要求外部资源的问题可能会被标记为离题，只是警告你。抱歉，我对加密/解密知之甚少。即使我的函数返回了一些东西，这也应该适用？您的加密函数应该返回加密字符串。

<input type="text" id="input"/>
<button type="button" onclick="encrypt()"/>
<div id="output"></div>

function encrypt() {
    var text = document.getElementById('input');

    var encrypted = convert1(text);

    document.getElementById('output').innerHTML = encrypted;
}

<input type="text" id="input"/>
<button type="button" onclick="encrypt()"/>
<div id="output"></div>

function encrypt() {
    var text = document.getElementById('input');

    var encrypted = yourEncryptFunction(text);

    document.getElementById('output').innerHTML = encrypted;
}