在JavaScript中繁瑣的時間解析

Question

我需要一個函數來將文本中的時間從具有日期字母的格式轉換爲數字。 例如4:15 PM - > 16:15，4:15 AM - > 4:15 AM。目前，我有以下解決方案

function formatTime(text){ 
 
\t var find = '([0-9]|0[0-9]|1[0-9]|2[0-3]):[0-5][0-9] (AM|PM)'; 
 
\t 
 
\t var reg = new RegExp(find, 'g'); 
 
\t 
 
\t pos = 0; 
 

 
\t var result; 
 
\t var formatedText = ""; 
 
\t while((result = reg.exec(text)) !== null) { 
 
\t \t if(result[2] == "PM"){ 
 
\t \t \t var hours= parseInt(result[0], 10); 
 
\t \t \t hours = hours + 12; 
 
\t \t \t var hoursStr = hours.toString(); 
 
\t \t \t var newTime = hoursStr + result[0].substring(result[1].length,result[0].length - 3); 
 
\t \t \t 
 
\t \t \t formatedText += newTime; 
 
\t \t \t pos = reg.lastIndex; 
 
\t \t } else { 
 
\t \t \t formatedText += text.replace("AM","").substring(pos, reg.lastIndex); 
 
\t \t \t pos = reg.lastIndex; 
 
\t \t } 
 
\t } 
 
\t 
 
\t if(pos < text.length){ 
 
\t \t formatedText += text.substring(pos, text.length); 
 
\t } 
 
\t 
 
\t return formatedText; 
 
} 
 

 
console.log(formatTime("Some Text (11:00AM - 1:00PM)"));

我做很好的情況下，像 的console.log（formatTime（ 「有些文字（11:00 AM - 1:00 PM）」））;但是我努力讓它進程 console.log（formatTime（「Some Text（11:00 AM - 1:00 PM）」））;

Answer 1

這適用於您的示例。 我已將\\s?添加到正則表達式中，並在切割時間的邏輯（-2而不是-3）上做了小的改動。此外，我已經將變量定義移至函數的開頭，以反映JavaScript中的提升。

function formatTime(text){ 
    var find = '([0-9]|0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]\\s?(AM|PM)';    
    var reg = new RegExp(find, 'g');    
    var pos = 0; 
    var formatedText = ""; 
    var result, hours, hoursStr, newTime;   

    while ((result = reg.exec(text)) !== null) { 
     if (result[2] === "PM") { 
      hours= parseInt(result[0], 10); 
      hours = hours + 12; 
      hoursStr = hours.toString(); 
      newTime = hoursStr + result[0].substring(result[1].length, result[0].length - 2); 

      formatedText += newTime;      
     } else { 
      formatedText += text.replace("AM","").substring(pos, reg.lastIndex); 

     } 

     pos = reg.lastIndex; 
    } 

    if (pos < text.length) { 
     formatedText += text.substring(pos, text.length); 
    } 

    return formatedText; 
} 

Answer 2

下面是一個更簡單的方法：使用兩個函數。一個轉換小時，另一個與PM次以及replace()函數匹配。

別逼我......

function convertTime12to24(time12h) { 
 
    const [time, modifier] = time12h.split(' '); 
 

 
    let [hours, minutes] = time.split(':'); 
 

 
    if (hours === '12') { 
 
    hours = '00'; 
 
    } 
 

 
    if (modifier === 'PM') { 
 
    hours = parseInt(hours, 10) + 12; 
 
    } 
 

 
    return hours + ':' + minutes; 
 
} 
 

 

 
function formatTime(i_string) { 
 
    console.log(i_string.replace(/([0-9]|0[0-9]|1[0-9]|2[0-3]):([0-5][0-9])(PM)/gi, function newDate(x) { 
 

 
    return convertTime12to24(x.replace("PM", " PM")) 
 
    })); 
 
} 
 
formatTime("The time is now 4:15PM"); 
 
formatTime("The time is now 12:15PM"); 
 
formatTime("The time is now 4:00AM"); 
 
formatTime("The time is now 12:00AM"); 
 
formatTime("The time is now 11:00PM");