作为程序员，没有合适的工具，就得手搓一个，PC端，移动端均可适用。废话不多说，直接上代码。
HTML:
<div class="calculator"><div><label>开始日期：</label><input id="startDate1" type="date"><label>结束日期：</label><input id="endDate1" type="date"><button onclick="calculateDateDifference()">计算天数差</button><div id="daysDifference" class="result"></div></div><div> </div><div><label>开始日期：</label><input id="startDate2" type="date"><label>输入天数：</label><input id="daysToAdd" type="number" value="1"><button onclick="calculateEndDate()">计算结束日期</button><div id="endDateResult" class="result"></div></div></div>
JS:
function calculateDateDifference() { const startDate1 = new Date(document.getElementById('startDate1').value); const endDate1 = new Date(document.getElementById('endDate1').value); const timeDifference = endDate1 - startDate1; const daysDifference = timeDifference / (1000 * 3600 * 24); document.getElementById('daysDifference').textContent = `两个日期之间的天数差为 ${daysDifference} 天。`; } function calculateEndDate() { const startDate2 = new Date(document.getElementById('startDate2').value); const daysToAdd = parseInt(document.getElementById('daysToAdd').value); const resultDate = new Date(startDate2); resultDate.setDate(resultDate.getDate() + daysToAdd); document.getElementById('endDateResult').textContent = `计算的结束日期是 ${resultDate.toISOString().split('T')[0]}。`; } function calculateStartDate() { const endDate2 = new Date(document.getElementById('endDate2').value); const daysToSubtract = parseInt(document.getElementById('daysToSubtract').value); const resultDate = new Date(endDate2); resultDate.setDate(resultDate.getDate() - daysToSubtract); document.getElementById('startDateResult').textContent = `计算的开始日期是 ${resultDate.toISOString().split('T')[0]}。`; }
CSS:
.calculator { width: 100%; background-color: #333; color: white; padding: 20px; border-radius: 10px; box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3); } label { display: block; margin-bottom: 10px; font-size: 16px; } input, select { width: 100%!important; padding: 10px!important; margin-bottom: 20px; color: #000000; border-radius: 5px; border: 1px solid #555; font-size: 16px!important; background-color: #ffffff!important; } button { width: 100%; padding: 10px; background-color: #007bff; color: white; border: none; border-radius: 5px; cursor: pointer; font-size: 16px; } button:hover { background-color: orange; } .result { font-size: 18px; margin-top: 20px; text-align: center; } option { background-color: #ffffff; } p { font-size: 18px; margin-top: 5px!important; }
