我的计算器有问题。按钮工作并且全部对齐，但我无法在监视器盒上显示任何内容或计算任何内容。我在下面列出了我的代码，谁能帮我找到我哪里出错了？我觉得这与真假有关，但我想不通。
这是 HTML 代码:
<body>
<table>
<tr>
<input id="display" type="text" value="0"/><span id="currOp"></span>
<tr>
<td>
<button id="7" class="num">7</button>
</td>
<td>
<button id="8" class="num">8</button>
</td>
<td>
<button id="9" class="num">9</button>
</td>
<td>
<button id="plus" class="operator">+</button>
</td>
<td>
<button id="clear">C</button>
</td>
</tr>
<tr>
<td>
<button id="4" class="num">4</button>
</td>
<td>
<button id="5" class="num">5</button>
</td>
<td>
<button id="6" class="num">6</button>
</td>
<td>
<button id="minus" class="operator">-</button>
</td>
<td>
<button id="root">√</button>
</td>
</tr>
<tr>
<td>
<button id="1" class="num">1</button>
</td>
<td>
<button id="2" class="num">2</button>
</td>
<td>
<button id="3" class="num">3</button>
</td>
<td>
<button id="mult" class="operator">x</button>
</td>
<td>
<button id="power" class="operator">x^y</button>
</td>
</tr>
<tr>
<td>
<button id="0" class="num">0</button>
</td>
<td>
<button id="decimal">.</button>
</td>
<td>
<button id="invert">±</button>
</td>
<td>
<button id="divid" class="operator">÷</button>
</td>
<td>
<button id="equals">=</button>
</td>
</tr>
这是CSS代码:
button {
height: 40px;
width: 40px;
font-size: 110%;
}
#display{
font-size: 120%;
text-align: right;
}
span {
font-size: 150%;
}
这是javascript代码:
var isOperating = true;
var isfloating = false;
var toBeCleared = true;
var operator;
var operand;
var display;
$(document).ready(init);
function init() {
display = $('#display');
$('.num').on('click', numClicked);
$('.operator').on('click', operatorClicked);
$('#invert').on('click', invertClicked);
$('#root').on('click', rootClicked);
$('#decimal').on('click', decimalClicked);
$('#equals').on('click', equalsClicked);
$('#clear').on('click', clearClicked);
}
function numClicked() {
var currVal = display.val();
var clickedNum = $(this).text();
if (currVal === "0" || toBeCleared) {
toBeCleared = true;
display.val(clickedNum);
} else {
display.val(currVal + clickedNum);
}
}
function invertClicked() {
display.val(display.val() * -1);
}
function rootClicked() {
display.val(Math.sqrt(evaluate()));
}
function decimalClicked() {
if (toBeCleared) {
display.val('0.');
toBeCleared = true;
} else {
if (!isFloating) {
display.val(display.val().concat('.'));
}
}
isFloating = false;
}
function equalsClicked() {
display.val(evaluate());
reset();
}
function clearClicked() {
reset();
display.val('0');
}
function reset() {
toBeCleared = true;
isOperating = true;
isFloating = false;
operator = null;
operand = null;
$('#currOp').text('');
}
function operatorClicked() {
if (isOperating) {
display.val(evaluate());
}
switch ($(this).attr('id')) {
case 'plus': operator = '+'; break;
case 'minus': operator = '-'; break;
case 'mult': operator = 'x'; break;
case 'divide': operator = '÷'; break;
case 'power': operator = '^'; break;
}
operand = parseFloat(display.val());
isOperating = true;
toBeCleared = true;
$('#currOp').text(operator);
}
function evaluate() {
`enter code here` var currVal = parseFloat(display.val());
var result;
switch (operator) {
case '+': result = operand + currVal; break;
case '-': result = operand - currVal; break;
case 'x': result = operand * currVal; break;
case '÷':
if (currVal === 0) {
result = 'Err';
} else {
result = operand / currVal;
}
break;
case '^': result = Math.pow(operand, currVal); break;
default: result = currVal;
}
return result;
}
最佳答案
您应该设置 toBeCleared = false;
if (currVal === "0" || toBeCleared) {
toBeCleared = false;
display.val(clickedNum);
} else {
display.val(currVal + clickedNum);
}
关于javascript - HTML、CSS、JavaScript 计算器，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/38442914/