[英]JavaScript - Print Odd & Even numbers preceding number input
我正在尝试将所有奇数和偶数（在 2 个不同的字段中）打印到用户输入的数字。
我有一切来验证输入（确保它是一个正的 2 位数字），如果我删除了代码中可见的 For 循环，我可以打印一条消息，但是当涉及到打印所有奇数和偶数时某个数字我现在真的被困了 2 天。
任何人都可以请指出我的方向吗？ 我不想要所有的代码，只是告诉我是否完全错误并且应该使用另一种方法已经对我有所帮助，但目前我无处可去，也找不到任何类似的问题。
到目前为止，这是我的全部代码（包括我尝试打印奇数和偶数失败）：
function myFunction() { var x, message; x = document.getElementById("positiveInteger").value; if (x == "") { alert("Input is empty. Please enter a positive 2 digit number."); } else if (isNaN(x)) { alert("Input is not a number. Please enter a positive 2 digit number."); } else if (x >= 1 && x <= 9) { alert("Input is too low. Please enter a positive 2 digit number."); } else if (x > 99) { alert("Input is too high. Please enter a positive 2 digit number."); } else if (x == 00) { alert("Input is not valid, 00 is not a positive number. Please enter a positive 2 digit number."); } else { for (i = 0; i < x; i + 2) { // This is my attempt to add 2 from 0 (hoping to get all even numbers) to each iteration until we reach the number input. message = document.getElementById("evenNumbers").innerHTML; } for (i = 1; i < x; i + 2) { // This is my attempt to add 2 from 1 (hoping to get all odd numbers) to each iteration until we reach the number input. message = document.getElementById("oddNumbers").innerHTML; } } }
<!DOCTYPE html> <html lang=en> <head> <meta charset="UTF-8"> <link type="text/css" rel="stylesheet" href=""> <style type="text/css"></style> <meta name="description" content="..." /> <meta name="keywords" content="" /> <title>Q2 - Two Digit Number</title> </head> <script> </script> <body> <h1>Welcome to C1 Assignment 2 - Question 2 !</h1> <p>Please enter a positive 2 digit number:</p> <input type="text" name="integer" id="positiveInteger"> <br><br> <button type="button" name="button" onclick="myFunction()">Submit</button> <br><br> <p id="oddNumbers"></p> <p id="evenNumbers"></p> </body> </html>
您有以下问题：
您没有分配给innerHTML ，您正在阅读它。
你没有在循环期间增加i 。 i + 2应该是i += 2 。
您需要将所有数字连接到message字符串中，然后再将其分配给输出元素的innerHTML 。
function myFunction() { var x, message; x = document.getElementById("positiveInteger").value; if (x == "") { alert("Input is empty. Please enter a positive 2 digit number."); } else if (isNaN(x)) { alert("Input is not a number. Please enter a positive 2 digit number."); } else if (x >= 1 && x <= 9) { alert("Input is too low. Please enter a positive 2 digit number."); } else if (x > 99) { alert("Input is too high. Please enter a positive 2 digit number."); } else if (x == 00) { alert("Input is not valid, 00 is not a positive number. Please enter a positive 2 digit number."); } else { message = ""; for (i = 0; i < x; i += 2) { message += i + " "; } document.getElementById("evenNumbers").innerHTML = message; message = ""; for (i = 1; i < x; i += 2) { message += i + " "; } document.getElementById("oddNumbers").innerHTML = message; } }
<h1>Welcome to C1 Assignment 2 - Question 2 !</h1> <p>Please enter a positive 2 digit number:</p> <input type="text" name="integer" id="positiveInteger"> <br><br> <button type="button" name="button" onclick="myFunction()">Submit</button> <br><br> Odd: <p id="oddNumbers"></p> Even: <p id="evenNumbers"></p>
如果其他数字是奇数，则返回“偶数”，而“奇数”其他数字是偶数 javascript
[英]return “even” if others numbers are odd and “odd” the others number are even javascript
来自javascript中数组的奇数位置具有偶数，偶数位置具有奇数
[英]odd positions has even numbers and even positions have odd number from an array in javascript
如何编写js代码以表格形式打印1到100的序号、奇数和偶数？
[英]How do I write js code to print serial number, odd numbers and even numbers from 1 to 100 in a tabular form?
在 javascript 中输入任意随机数后，如何得到下一个“十”奇数和偶数的 output
[英]how to get an output of next `ten` odd and even numbers after entering any random number in javascript
JavaScript：用户输入数字，直到输入0。确定每个数字的奇偶性，最后打印偶数和奇数的总数
[英]JavaScript:User enters numbers until he enters 0.Each numbers parity is determined and at the end,the total number of even and odd numbers is printed
声明:本站的技术帖子网页，遵循CC BY-SA 4.0协议，如果您需要转载，请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.