Javascript:数组无法使用表单
我目前正在做一个程序，该程序将在一个新窗口中显示用户输入范围内的素数和回文素数，以下是我迄今为止的代码：Javascript:数组无法使用表单,javascript,arrays,primes,palindrome,Javascript,Arrays,Primes,Palindrome,我目前正在做一个程序，该程序将在一个新窗口中显示用户输入范围内的素数和回文素数，以下是我迄今为止的代码： <!DOCTYPE html> <html> <head> <meta charset = "utf-8"> <title> 9.25 Excercise </title> <script type = "text/javascript"> <!-
<!DOCTYPE html>
<html>
<head>
<meta charset = "utf-8">
<title> 9.25 Excercise </title>
<script type = "text/javascript">
<!-- Begin
var arrayLength = (parseInt(form.endNum.value))-(parseInt(form.startNum.value));
var num=new Array(arrayLength);
var number1=parseInt(form.startNum.value);
for (var y=0; y<arrayLength; y++){
num[y] = number1;
number1++;
}
function calculate1(form) {
var newWindow = window.open("","Test","width=300,height=300,scrollbars=1,resizable=1");
newWindow.document.write("Prime: <br> <br>");
for (y=0; y<arrayLength; y++)
if (num[y] == 1) {
newWindow.document.write(num[y]);
}
for (var i=2;i<num[y];i++) {
if (num[y] % i == 0) {
var prime="yes";
newWindow.document.write(num[y]);
break;
}
if (num[y] % i != 0) var prime="no";
}
}
// End -->
</script>
</head>
<body>
<form name=form>
This Program finds Prime numbers and Palindromic numbers between two integers.<br>
Maximum range between the integers is 999.<br>
<hr />
Starting Value (>0): <input type="number" name="startNum" min="1" max="99999"> Ending Value (<= 99999): <input type="number" name="endNum" min="1" max="99999"> <br> <br>
<input type=button value="Find Primes" onClick="calculate1(this.form)">
<input type=button value="Find Palindromic Primes Only" onClick="calculate2(this.form)">
<input type=button value="Find Both" onClick="calculate3(this.form)">
</form>
</body>
可能Javascript开头的注释会影响代码的行为。这不是您在JavascriptCheck浏览器控制台中的注释方式。你至少有3个错误。像parseIntform.endNum.value一样，表单没有定义，表单标记中缺少引号。此外，calculate1应该在var arraylenght之前开始。什么意思没有定义表单？@TheOniStixx您在var arrayleength=parseIntform.endNum.value中使用表单，但从未声明过var表单。好吧，尽管现在进行了所有这些更改，但如果范围从1到任何值，它只会显示数字1，否则它仍然不会显示任何内容只是将其转换为字符串，然后将其反转。。请参阅我答案第一行上面的链接。。
<!DOCTYPE html>
<html>
<head>
<meta charset = "utf-8">
<title> 9.25 Excercise </title>
<script type = "text/javascript">
//* <!-- Begin
function calculate_prime(form) {
var newWindow = window.open("","Test","width=300,height=300,scrollbars=1,resizable=1");
var doc = newWindow.document;
doc.write("Prime: <br> <br>");
var nstart = parseInt(form.startNum.value);
var nend = parseInt(form.endNum.value);
// give initial prime numbers, more is better
var prime = [2,3,5,7,11,13,17,19,23];
// check with previous primes
for(var z = prime[prime.length-1] + 2; z <= nend; z += 2) {
var is_prime = true;
// if current number divisible by previous primes
for(var y = 1; y < prime.length; ++y) {
// skip when divisor larger than half of z
if(prime[y]>z/2) break;
// if z divisible, then is not a prime
if(z%prime[y] == 0) {
is_prime = false;
break;
}
}
// if a prime, add it to our array
if(is_prime) {
prime.push(z);
}
}
// print all primes within the range
for (var z = 0; z<prime.length; ++z) {
if(prime[z] < nstart) continue;
doc.write(prime[z] + ' ');
}
}
// End --> */
</script>
</head>
<body>
<form name='form'>
This Program finds Prime numbers and Palindromic numbers between two integers.<br>
Maximum range between the integers is 999.<br>
<hr />
Starting Value (>0): <input type="number" name="startNum" min="1" max="99999" value='1'> Ending Value (<= 99999): <input type="number" name="endNum" min="1" max="99999" value='99999'> <br> <br>
<input type=button value="Find Primes" onClick="calculate_prime(this.form)">
<input type=button value="Find Palindromic Primes Only" onClick="calculate2(this.form)">
<input type=button value="Find Both" onClick="calculate3(this.form)">
</form>
</body>
</html>