javascript - 使用 JavaScript 捕获文本框的值

Question

我正在尝试显示一个按钮和文本框。让用户输入一个数字。将生成一个随机数，并且用户有 10 次尝试正确回答问题的机会。该脚本应检查用户数量是否等于、小于或大于随机数。我无法获取从文本框中输入的号码。

HTML:

<form name="myForm">
        <div id='myForm'></div>
</form>

JavaScript:

   function partC(){
            var guessCount = 10;
            var random = Math.round(Math.random()*100);

            var button = document.createElement('input');
            button.type = "button";
            button.value = " Guess! ";
            document.getElementById('myForm').appendChild(button);
            var textbox = document.createElement('input');
            textbox.type = 'number';
            document.getElementById('myForm').appendChild(textbox);
            var check = document.getElementById('textbox').value
            button.onclick = calc(guessCount, random, check);

    }

    function calc(guessCount, random, check){
        while(guessCount > 0) {
                if (check == random){
                    alert("Correct!");
                } else if (check > random) {
                    alert("Try Again. Guess to High. " + guessCount + " tries left.");
                } else if (check < random) {
                    alert("Try Again. Guess to Low. " + guessCount + " tries left.");
                }
            guessCount--;

        }   
    }

Answer 1

您的代码将回调函数结果分配给 onclick 事件而不是函数本身。此外，您还尝试运行一个 while 循环，该循环将消耗第一次单击事件上的guessCount。

我编辑了代码，以下应该可以工作:

   function partC(){
            var guessCount = 10;
            var random = Math.round(Math.random()*100);
            var button = document.createElement('input');
            button.type = "button";
            button.value = " Guess! ";
            document.getElementById('myForm').appendChild(button);
            var textbox = document.createElement('input');
            textbox.type = 'number';
            document.getElementById('myForm').appendChild(textbox);
            button.onclick = function(){
            var check = textbox.value*1;
            if (check == random){
                    alert("Correct!");
                } else if (check > random) {
                    alert("Try Again. Guess to High. " + guessCount + " tries left.");
                } else if (check < random) {
                    alert("Try Again. Guess to Low. " + guessCount + " tries left.");
                }
            guessCount--;

            }

    }