如何使用 JavaScript 通过以 mm/dd/yyyy 格式将天数（项目持续时间）添加到当前日期来查找项目完成日期？

Question

我目前正在为网页设计前景和 JavaScript 新手制作报价表，并且一直在使用 JavaScript 根据项目持续时间（天数）+项目开始日期的总和来确定项目完成日期（默认设置为今天的日期，格式为mm/dd/yyyy ）。

非常感谢有经验的帮手来解决这个初学者的问题。

 function SetDate() { var date = new Date(); var day = date.getDate(); var month = date.getMonth() + 1; var year = date.getFullYear(); if (month < 10) month = "0" + month; if (day < 10) day = "0" + day; var today = month + "-" + day + "-" +year; document.getElementById('Date').value = today; document.getElementById('Project_Start_Date').value = today; }

 <td>Projected Duration Estimate**:</td> <td><input type="text" name="Projected Duration" id="Projected_Duration"><label> Days</label></td> <td>Project Start Date:</td> <td><input type="text" name="Project Start Date" id="Project_Start_Date"></td> <td>Project Completion Date:</td> <td><input type="text" name="Project Completion Date" id="Project_Completion_Date"></td>

Answer 1

为此使用 moment.js 的 add， moment().add(7, 'days')

// 它为您提供从当前日期起 7 天后的日期）

参考链接https://momentjs.com/docs/#/manipulating/add/

Answer 2

处理日期时， moment非常棒。

 function render() { const estimate = parseInt(document.getElementById("Projected_Duration").value); const startDateStr = document.getElementById("Project_Start_Date").value; if(startDateStr) { const startDate = moment(startDateStr); let endDate = startDate.add(estimate, 'day').format('YYYY-MM-DD'); document.getElementById("Project_Completion_Date").value = endDate; } }

 <script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.24.0/moment-with-locales.min.js"></script> <td>Projected Duration Estimate**:</td> <td><input type="number" min="0" name="Projected Duration" id="Projected_Duration" onchange="render()"><label> Days</label></td> <td>Project Start Date:</td> <td><input type="date" name="Project Start Date" id="Project_Start_Date" onchange="render()"></td> <td>Project Completion Date:</td> <td><input type="date" name="Project Completion Date" id="Project_Completion_Date" readonly></td>