使用 &letter; JavaScript 中的符号不写希腊字母

Question

When I set an input box value with the "value" attribute in HTML to a greek letter, it shows the greek letter correctly. But when I change the "value" attribute with JavaScript, it uses the "&letter;" format. What can I do so that JavaScript behaves just as HTML?

HTML: <input type="text" id="input" value = "&epsilon;"> works fine. JavaScript: document.getElementById("input").value = "ε"; shows ε but not the greek letter

Answer 1

The problem you're facing occurs because of the way you're setting the input. Javascript is (correctly) treating your ε as an ordinary string, because you haven't told it that it's anything else.

If this were an element like p , or span or any other contextual text element, you could simply do

myElem.innerHTML = "ε";

However, since you want to set this to be the input's value, you can't use innerHTML , because it wouldn't make any sense. What you need to do is something like this.

 function htmlDecode(input) { var doc = new DOMParser().parseFromString(input, "text/html"); return doc.documentElement.textContent; } document.getElementById("myInput").value = htmlDecode("ε");

 <input type="text" id="myInput" name="myInput" value="">

The function I used was originally posted in this SO answer . Be sure to read the rest of it, to see the other uses.