JavaScript 获取日期之间的相对时间差

给定两个JavaScript日期，任务是获取它们之间的相对时间差（例如2小时前，2.5天前等）。这里讨论了两种使用JavaScript的方法。

方法1

使用Date()对象将prevDate和currDate存储在变量中。
计算分钟、小时、天、月和年的毫秒数。
计算prevDate和currDate之间的毫秒差。
按顺序将这些毫秒数与分钟、小时、天、月和年的毫秒数进行比较。
如果毫秒数小于任何一个值，则计算相应的分钟、小时、天、月和年。

示例1： 这个示例实现了上述方法。

<body> 
    <h1 style="color:green;"> 
        GeeksforGeeks 
    </h1> 
    <p id="GFG_UP"> 
    </p> 
    <button onclick="GFG_Fun();"> 
        click here 
    </button> 
    <p id="GFG_DOWN"> 
    </p> 
    <script> 
        var up = document.getElementById('GFG_UP'); 
        var down = document.getElementById('GFG_DOWN'); 
        var prevDate = new Date(); 
        prevDate.setDate(prevDate.getDate() - 6); 
        up.innerHTML = 
            "Click on the button to get relative time difference between dates." + 
            "<br><br>Older Date : " + prevDate; 
          
        function timeDiff(curr, prev) { 
            var ms_Min = 60 * 1000; // milliseconds in Minute 
            var ms_Hour = ms_Min * 60; // milliseconds in Hour 
            var ms_Day = ms_Hour * 24; // milliseconds in day 
            var ms_Mon = ms_Day * 30; // milliseconds in Month 
            var ms_Yr = ms_Day * 365; // milliseconds in Year 
            var diff = curr - prev; //difference between dates. 
            // If the diff is less then milliseconds in a minute 
            if (diff < ms_Min) { 
                return Math.round(diff / 1000) + ' seconds ago'; 
          
                // If the diff is less then milliseconds in a Hour 
            } else if (diff < ms_Hour) { 
                return Math.round(diff / ms_Min) + ' minutes ago'; 
          
                // If the diff is less then milliseconds in a day 
            } else if (diff < ms_Day) { 
                return Math.round(diff / ms_Hour) + ' hours ago'; 
          
                // If the diff is less then milliseconds in a Month 
            } else if (diff < ms_Mon) { 
                return 'Around ' + Math.round(diff / ms_Day) + ' days ago'; 
          
                // If the diff is less then milliseconds in a year 
            } else if (diff < ms_Yr) { 
                return 'Around ' + Math.round(diff / ms_Mon) + ' months ago'; 
            } else { 
                return 'Around ' + Math.round(diff / ms_Yr) + ' years ago'; 
            } 
        } 
          
        function GFG_Fun() { 
            var diff = timeDiff(new Date(), prevDate) 
            document.getElementById("GFG_DOWN").innerHTML = diff; 
        } 
    </script> 
</body>

输出：

JavaScript 获取日期之间的相对时间差

方法2

将prevDate和currDate存入一个变量中。
计算日期之间的秒数、分钟数、小时数和天数差异。
按照60秒、60分钟、24小时、一天的顺序，比较这些参数。
如果其中任何条件满足，则返回相应的参数。

示例2： 此示例实现了上述方法。

<body> 
    <h1 style="color:green;"> 
        GeeksforGeeks 
    </h1> 
    <p id="GFG_UP"> 
    </p> 
    <button onclick="GFG_Fun()"> 
        click here 
    </button> 
    <p id="GFG_DOWN"> 
    </p> 
    <script> 
        var up = document.getElementById('GFG_UP'); 
        var down = document.getElementById('GFG_DOWN'); 
        var prevDate = new Date(); 
        prevDate.setDate(prevDate.getDate() - 6); 
        prevDate.setHours(prevDate.getHours() - 6); 
        up.innerHTML = 
            "Click on the button to get relative time " + 
            "difference between dates.<br><br>Older Date : " + prevDate; 
          
        function conversion(ms) { 
          
            // Calculating Seconds 
            var sec = (ms / 1000).toFixed(1); 
          
            // Calculating Minutes 
            var min = (ms / (1000 * 60)).toFixed(1); 
          
            // Calculating hours 
            var hrs = (ms / (1000 * 60 * 60)).toFixed(1); 
          
            // Calculating days 
            var days = (ms / (1000 * 60 * 60 * 24)).toFixed(1); 
            if (sec < 60) { 
                return sec + " Sec"; 
            } else if (min < 60) { 
                return min + " Min"; 
            } else if (hrs < 24) { 
                return hrs + " Hrs"; 
            } else { 
                return days + " Days" 
            } 
        } 
          
        function GFG_Fun() { 
            var date = new Date(); 
            var diff = conversion(date.getTime() - prevDate.getTime()) 
            document.getElementById("GFG_DOWN").innerHTML = diff; 
        } 
    </script> 
</body>