結合for循環，更改爲「while循環」，保持功能

Question

有沒有簡單的方法將這三個循環合成一個？然後將它們更改爲「while循環」，同時保持相同的功能？

我試圖將數據轉換成這樣：

{ run = true; counter = 1; while (run == true) /* or while (run) */ {document.write (counter); 
counter++; if (counter > 3) run = false; } // end loop /* How many times will this loop go? */ } 

但只得到一個空白頁。

這裏是原始的「for循環」代碼;

//numbers divisible by 5 
for (i=1; i<=50; i++) { 
if (i%5 == 0) document.write ("number divisible by five is: " + i + "<br />") ; 
} //for 
document.write ("========================<br />"); //seperator 

//numbers divisible by 7 
for (i=1; i<=50; i++) { 
if (i%7==0) && (i%2!=0)) document.write ("number divisible by seven is: " + i + "<br />") ; 
} //for 
document.write ("========================<br />"); //seperator 

//numbers divisible by 9 
for (i=1; i<=50; i++) { 
if (i%9==0) && (i%2==0)) document.write ("number divisible by nine is: " + i + "<br />") ; 
} //for 
document.write ("========================<br />"); //seperator 

Answer 1

如果你想在循環結合起來，把三個if語句爲從1到50

一個單迴路要轉換的for循環while循環，直接翻譯過來的樣子所以

i = 1; // variable 
while (i<=50) { // condition 
    if (i%5 == 0) document.write ("number divisible by five is: " + i + "<br />") ; 
    // more if statements 
    i++; // increment 
} 

Answer 2

也許試試這個？

var divisions = { 
    five: [], 
    seven:[], 
    nine: [] 
}; 

for(i = 1; i <= 50; i ++;){ 
    if(i % 5 == 0) divisions.five.push(i); 
    if((i % 7 == 0) && (i % 2 != 0)) divisions.seven.push(i); 
    if((i % 9 == 0) && (i % 2 == 0)) divisions.nine.push(i); 
} 

divisions.five.forEach(function(number){ 
    document.write('number divisible by 5 is:' + number); 
}); 

document.write ("========================<br />"); //seperator 

divisions.seven.forEach(function(number){ 
    document.write('number divisible by 7 is:' + number); 
}); 

document.write ("========================<br />"); //seperator 

divisions.nine.forEach(function(number){ 
    document.write('number divisible by 9 is:' + number); 
}); 

document.write ("========================<br />"); //seperator 

我沒有測試過這一點，寫在文本框中這裏，你應該得到的總體思路。