需要替换字符但替换不起作用

Question

好的，所以我有一些JavaScript，基本上它从一个网站获得一个数学公式，将其更改为eval()，然后通过eval进行读取，然后当我按一个键将eval()的答案插入到输入框中。我有一个问题是，（例如）y +？ = 20。“y”从数字1-20变化。到目前为止，代码得到了这个问题的答案，但是以负面的形式。 （例如：14 +？= 20 = -14）。所以我需要帮助从我的答案中删除所有“ - ”字符。

代码变量：

var inputBox = where the answer is (like -14 in my case)  
var question = the question. in my case 14 + ? = 20  

到目前为止的代码：

//Mathletics Level 4 with Blocks// 
function showAnswer(){ 

var inputBox = document.getElementsByClassName("questions-input-adjustment questions-input-width-v3")[0]; 
var submitButton = document.getElementsByClassName('question-input-form')[0]; 
for (var i = 0; i < 100; i++) { 
    var question = document.getElementsByClassName("questions-text-alignment whiteTextWithShadow question-size-v4")[0].innerText; 
    question = question.replace('= 20', '-20') 
    question = question.replace('×', '*') 
    question = question.replace('=', ''); 
    question = question.replace('=', ''); 
    var answer = eval(question) 
    inputBox.value = answer; 

var awnser = addbits(equasion) 

var inputBox = document.getElementsByClassName("questions-input-adjustment questions-input-width-v3")[0]; 
var submitButton = document.getElementsByClassName('question-input-form')[0]; 
for (var i = 0; i < 100; i++) { 
    var question = document.getElementsByClassName("questions-text-alignment")[0].innerText; 
    question = question.replace('= 20', '-20') 
    question = question.replace(' =', ''); 
    question = question.replace('×', '*') 
    question = question.replace('=', ''); 
    inputBox.value = answer; 

} 

var awnser = addbits(equasion) 

document.getElementById('dashow').innerText = awnser; 
document.getElementsByClassName("questions-input-adjustment questions-input-width-v3")["0"].value = awnser; 
} 

window.addEventListener("keydown", checkKeyPressed, false); 

function checkKeyPressed(e) { 
    if (e.keyCode == "81") { 
     showAnswer() 
    } 
} 

Answer 1

试试这个：

myanswer= myanswer.replace(/-/g,''); 

它的答案reomve负

Answer 2

你可以删除减去使用下面的abs乐趣ction

  a =-3 
 
      x=Math.abs(a); 
 
      console.log(x)