使用表单收集Javascript函数的数据？
作者：互联网
我正在尝试通过一页上的表单收集数据,然后将该数据传输到下一页以在JS函数中使用.
(特别是,我希望用户输入二次方程式的A,B和C的值,然后发送到页面,脚本将在其中获取这些值并运行方程式以输出答案).
这是我第一页的代码—>
<body>
<h1> Welcome to the Math Equation Solver </h1>
<p> Which equation would you like to solve? (Simply input the data for the equation you wish to solve). </p>
<form name="quad" method="get" action="JS_B.html">
<input
<input type="text" name="a_val" size="5">
<br>
<input type="text" name="b_val" size="5">
<br>
<input type="text" name="c_val" size="5">
<br>
<input type="submit" method="get" action="JS_B.html" value="Submit">
<input type="hidden" name="a_val">
<input type="hidden" name="b_val">
<input type="hidden" name="c_val">
</form>
这是第二页的代码—>
<title>JS_Math Scripts</title>
<body>
<script type="Javascript">
function answer()
{
var a = a_val
document.writeln(a_val)
var b = b_val
var c = c_val
var root = Math.pow(b, 2) - 4 * a * c
var answer1 = (-b + Math.sqrt(root)) / 2*a
var answer2 = (-b - Math.sqrt(root)) / 2*a
if(root<'0');
{
alert('This equation has no real solution.')
}else{
if(root=='0')
{
answerOne = answer1
document.writeln(answerOne)
answerTwo = 'No Second Answer'
}else{
answerOne = answer1
document.writeln(answerOne)
answerTwo = answer2
document.writeln(answerTwo)
}
}
}
// End -->
</script>
<input type="hidden" name="a_val">
<input type="hidden" name="b_val">
<input type="hidden" name="c_val">
<input type="hidden" name="answerOne">
<input type="hidden" name="answerTwo">
<input type="hidden" name="Answer">
</body>
</html>
因此,无论如何,当我输入A,B和C的值时,它将带我到第二页,但没有得到结果.我已经尝试过检查元素,并且控制台未指示任何错误,所以我认为我的数据正在正确传输.有任何想法吗？
解决方法:
您可以使用FormData()从< input>中检索值. < form>中的元素；使用JSON.stringify(),encodeURIComponent()将值从表单作为查询字符串传递给JS_B.html.
在JS_B.html的窗口加载事件发生时,使用decodeURIComponent(),JSON.parse()在location.search检索对象.解构分配以使用传递的对象在答案函数中设置变量.
包括;按照变量分配,删除；如果条件以下
的index.html
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<h1> Welcome to the Math Equation Solver </h1>
<p> Which equation would you like to solve? (Simply input the data for the equation you wish to solve). </p>
<form name="quad">
<input type="text" name="a_val" size="5">
<br>
<input type="text" name="b_val" size="5">
<br>
<input type="text" name="c_val" size="5">
<br>
<input type="submit" value="Submit">
<!--
<input type="hidden" name="a_val">
<input type="hidden" name="b_val">
<input type="hidden" name="c_val">
-->
</form>
<script>
var form = document.querySelector("form");
form.onsubmit = function(e) {
e.preventDefault();
var data = new FormData(this);
var obj = {};
for (prop of data.entries()) {
obj[prop[0]] = prop[1]
};
var query = encodeURIComponent(JSON.stringify(obj));
location.href = "JS_B.html?" + query;
}
</script>
</body>
</html>
JS_B.html
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<script>
function answer(obj) {
var {
a_val: a,
b_val: b,
c_val: c
} = obj;
document.writeln(a);
var root = Math.pow(b, 2) - 4 * a * c;
var answer1 = (-b + Math.sqrt(root)) / 2 * a;
var answer2 = (-b - Math.sqrt(root)) / 2 * a;
if (root < 0) {
alert('This equation has no real solution.')
} else {
if (root == 0) {
answerOne = answer1;
document.writeln(answerOne);
answerTwo = 'No Second Answer'
} else {
answerOne = answer1;
document.writeln(answerOne);
answerTwo = answer2;
document.writeln(answerTwo)
}
}
} // End -->
window.onload = function() {
var obj = JSON.parse(decodeURIComponent(location.search.slice(1)));
console.log(obj);
answer(obj);
}
</script>
<input type="hidden" name="a_val">
<input type="hidden" name="b_val">
<input type="hidden" name="c_val">
<input type="hidden" name="answerOne">
<input type="hidden" name="answerTwo">
<input type="hidden" name="Answer">
</body>
</html>
plnkr http://plnkr.co/edit/aaY5rcJ6v0g7bdEEr7h0?p=preview
标签：html,javascript,forms,equations 来源： https://codeday.me/bug/20191013/1904410.html