的Javascript回用日期（）

Question

我有一個遞歸的JavaScript函數問題未定義的遞歸函數 - 返回值是不確定的：

function get_next_weekday(timesec) { 

    var nextdaytogo = timesec; 
    var nextday; 
    var hour = timesec.getHours(); 
    initstunden = 13 - hour; 
    initminuten = 59 - timesec.getMinutes(); 
    var holidays = [ 
     new Date(2016, 11, 25).toDateString(), new Date(2016, 11, 26).toDateString(), new Date(2017, 00, 01).toDateString(), new Date(2017, 00, 06).toDateString(), 
     new Date(2017, 03, 14).toDateString(), new Date(2017, 03, 17).toDateString(), new Date(2017, 04, 01).toDateString(), new Date(2017, 04, 25).toDateString(), 
     new Date(2017, 05, 05).toDateString(), new Date(2017, 05, 15).toDateString(), new Date(2017, 09, 03).toDateString(), new Date(2017, 10, 01).toDateString(), 
     new Date(2017, 11, 25).toDateString(), new Date(2017, 11, 26).toDateString(), new Date(2018, 00, 01).toDateString(), new Date(2018, 00, 06).toDateString(), 
     new Date(2018, 02, 30).toDateString(), new Date(2018, 03, 02).toDateString(), new Date(2018, 04, 01).toDateString(), new Date(2018, 04, 10).toDateString(), 
     new Date(2018, 04, 21).toDateString(), new Date(2018, 04, 31).toDateString(), new Date(2018, 09, 03).toDateString(), new Date(2018, 10, 01).toDateString(), 
     new Date(2018, 11, 25).toDateString(), new Date(2018, 11, 26).toDateString() 
    ]; 


    if ($.inArray(timesec.toDateString(), holidays) > -1 || timesec.getDay() == 0 || timesec.getDay() == 6) { 
     console.log("if() Statement") 
     //Holiday 
     if ($.inArray(timesec.toDateString(), holidays) > -1){ 
      console.log("Holiday Func." + timesec); 
      var nextday = new Date(timesec.getTime() + 24 * 60 * 60 * 1000); 
      var next = get_next_weekday(nextday); 

     } 
     //Sunday 
     else if (timesec.getDay() == 0){ 
      console.log("Sunday Func." + timesec); 
      var nextday = new Date(timesec.getTime() + 24 * 60 * 60 * 1000); 
      var next = get_next_weekday(nextday); 

     } 
     //Saturday 
     else if (timesec.getDay() == 6){ 
      console.log("Saturday Func." + timesec); 
      var nextday = new Date(timesec.getTime() + 24 * 60 * 60 * 1000); 
      var next = get_next_weekday(nextday); 

     } 
     else console.log("Und. Func."); 


    } 
    else{ 
     console.log("else Statement - Value: " + next); 
     return timesec; 
    } 
} 

var daydeliver = get_next_weekday(aktuell); 
console.log("Func. - Return: " + daydeliver); 

這是日誌：

1. 如果（ ）聲明SaturdayFunc.Sat Dec 23 2017 11:11:53 GMT + 0100 if（） Statement Sunday Func.Sun Dec 24 2017 11:11:53 GMT + 0100 if（） Statement Holiday Func.Mon Dec 25 2017 11： 11:53 GMT + 0100 if（） Statement Holiday Func.Tue Dec 26 2017 11:11:53 GMT + 0100 else 語句 - 值：undefined Func。 - Return：undefined

有人可以幫我解決這個問題嗎？

Answer 1

這是因爲您在本地範圍內聲明瞭var，並且在遞歸fn觸發時您不返回任何內容。我想你想要next從遞歸fn保存以前的日期。請檢查這一個：

//next will return undefined if no recursive function called 
 
var next; 
 
function get_next_weekday(timesec) { 
 

 
    var nextdaytogo = timesec; 
 
    var nextday; 
 
    var hour = timesec.getHours(); 
 
    initstunden = 13 - hour; 
 
    initminuten = 59 - timesec.getMinutes(); 
 
    var holidays = [ 
 
     new Date(2016, 11, 25).toDateString(), new Date(2016, 11, 26).toDateString(), new Date(2017, 00, 01).toDateString(), new Date(2017, 00, 06).toDateString(), 
 
     new Date(2017, 03, 14).toDateString(), new Date(2017, 03, 17).toDateString(), new Date(2017, 04, 01).toDateString(), new Date(2017, 04, 25).toDateString(), 
 
     new Date(2017, 05, 05).toDateString(), new Date(2017, 05, 15).toDateString(), new Date(2017, 09, 03).toDateString(), new Date(2017, 10, 01).toDateString(), 
 
     new Date(2017, 11, 25).toDateString(), new Date(2017, 11, 26).toDateString(), new Date(2018, 00, 01).toDateString(), new Date(2018, 00, 06).toDateString(), 
 
     new Date(2018, 02, 30).toDateString(), new Date(2018, 03, 02).toDateString(), new Date(2018, 04, 01).toDateString(), new Date(2018, 04, 10).toDateString(), 
 
     new Date(2018, 04, 21).toDateString(), new Date(2018, 04, 31).toDateString(), new Date(2018, 09, 03).toDateString(), new Date(2018, 10, 01).toDateString(), 
 
     new Date(2018, 11, 25).toDateString(), new Date(2018, 11, 26).toDateString() 
 
    ]; 
 

 

 
    if ($.inArray(timesec.toDateString(), holidays) > -1 || timesec.getDay() == 0 || timesec.getDay() == 6) { 
 
     console.log("if() Statement") 
 
     //Holiday 
 
     if ($.inArray(timesec.toDateString(), holidays) > -1){ 
 
      console.log("Holiday Func." + timesec); 
 
      let nextday = new Date(timesec.getTime() + 24 * 60 * 60 * 1000); 
 
      next = timesec; 
 
      return get_next_weekday(nextday); 
 

 
     } 
 
     //Sunday 
 
     else if (timesec.getDay() == 0){ 
 
      console.log("Sunday Func." + timesec); 
 
      let nextday = new Date(timesec.getTime() + 24 * 60 * 60 * 1000); 
 
      next = timesec; 
 
      return get_next_weekday(nextday); 
 

 
     } 
 
     //Saturday 
 
     else if (timesec.getDay() == 6){ 
 
      console.log("Saturday Func." + timesec); 
 
      let nextday = new Date(timesec.getTime() + 24 * 60 * 60 * 1000); 
 
      next = timesec; 
 
      return get_next_weekday(nextday); 
 

 
     } 
 
     else {console.log("Und. Func."); 
 
      next = "Und. Func.";return; 
 
      } 
 
    } 
 
    else{ 
 
     console.log("else Statement - Value: " + next); 
 
     return timesec; 
 
    }  
 
} 
 

 
var daydeliver = get_next_weekday(new Date(2016, 11, 11)); 
 
console.log("Func. - Return: " + daydeliver);

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