的Javascript回用日期（）

Question

我有一个递归的JavaScript函数问题未定义的递归函数 - 返回值是不确定的：

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); 

这是日志：

1. 如果（ ）声明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 语句 - 值：undefined Func。 - Return：undefined

有人可以帮我解决这个问题吗？

Answer 1

这是因为您在本地范围内声明了var，并且在递归fn触发时您不返回任何内容。我想你想要next从递归fn保存以前的日期。请检查这一个：

//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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