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JavaScript:当我已经有onclick事件时,如何添加keypress事件?

addeventlistener keypress onclick javascript-events javascript

0

00Saad · 技术社区 · 8 年前

当用户单击按钮时,它可以正常工作,但我也希望用户按下这些键。我不知道怎样才能顺利地做到这一点。

const a = document.getElementsByTagName('input');

// button press conditions
for (let i = 0; i < a.length; i++) {
    a[i].addEventListener('click', function(e) {
        // operators
        if (a[i].value === '+' ||
            a[i].value === '-' ||
            a[i].value === 'Ã' ||
            a[i].value === 'Ã·') {
                prsOpr(i);
        }

        // decimal button
        else if (a[i].value === '.') prsDeci(i);

        // equal button
        else if (a[i].value === '=') prsEql(i);

        // backspace button
        else if (a[i].value === 'â') prsBksp();

        // clear button
        else if (a[i].value === 'Clear') prsClr();

        // any number button
        else logNum(i);
    });
};

1 回复 | 直到 6 年前

1

Scott Marcus 8 年前

.addEventListener() 把它(和第一个)指向同一个函数:

举个例子:

let input = document.querySelector("input");

input.addEventListener("click", foo);    // Set up a click event handler
input.addEventListener("keydown", foo);  // Set up a key down event handler

// Both event registrations point to this one function as their callback
// so, no matter whether you click or type in the field, this function 
// will run. But, all event handlers are passed a reference to the event
// that triggered them and you can use that event to discern which action
// actually took place.
function foo(evt){
  console.log("The " + evt.type + " event has been triggered.");
}

<input>