我有以下html5输入元素:
<input type="number">
为什么这个输入允许在输入字段中输入字符“e”?无法输入其他字母字符(如预期的那样)
使用chrome v. 44.0.2403.107
下面的例子来看看我的意思。
= >“当家”型输入<
当前回答
HTML输入数字类型允许“e/ e”，因为“e”代表指数，这是一个数字符号。
例200000也可以写成2e5。我希望这能帮到你，谢谢你的问题。
其他回答
因为这正是规范所规定的。数字输入可以接受浮点数，包括负号和e或e字符(其中指数是e或e后面的数字):
A floating-point number consists of the following parts, in exactly the following order: Optionally, the first character may be a "-" character. One or more characters in the range "0—9". Optionally, the following parts, in exactly the following order: a "." character one or more characters in the range "0—9" Optionally, the following parts, in exactly the following order: a "e" character or "E" character optionally, a "-" character or "+" character One or more characters in the range "0—9".
使用angular，你可以限制输入e，+，-， e
<input type="number" (keypress)="numericOnly($event)"/>
numericOnly(event): boolean { // restrict e,+,-,E characters in input type number
debugger
const charCode = (event.which) ? event.which : event.keyCode;
if (charCode == 101 || charCode == 69 || charCode == 45 || charCode == 43) {
return false;
}
return true;
}
<input type="number" onkeydown="return FilterInput(event)" onpaste="handlePaste(event)" >
function FilterInput(event) {
var keyCode = ('which' in event) ? event.which : event.keyCode;
isNotWanted = (keyCode == 69 || keyCode == 101);
return !isNotWanted;
};
function handlePaste (e) {
var clipboardData, pastedData;
// Get pasted data via clipboard API
clipboardData = e.clipboardData || window.clipboardData;
pastedData = clipboardData.getData('Text').toUpperCase();
if(pastedData.indexOf('E')>-1) {
//alert('found an E');
e.stopPropagation();
e.preventDefault();
}
};
<input type="number" onkeydown="javascript: return ['Backspace'，'Delete'，'ArrowLeft'，'ArrowRight'].includes(event.code) ?isNaN(Number(event.key)) && event.code!= =‘空间’" / >
E代表指数，用来缩短长数字。因为输入是数学输入而指数在数学中是用来缩短数字的，所以这里有个E。
显示如下:4e。
链接:1和2
