JavaScript中的循环

我确切地知道如何编写for循环和while循环，但是我很难理解后面的内容。例如，我做了一个交互式教程，要求我编写一个For循环，将数字1添加到10

这是for循环的语法：

{ 
    var currentSum = 0;
    for (var i=1; i<= num; i++) {
        currentSum += i; // <--
    }
    return current sum  // <--
}
console.log(sum(10))

{
var currentSum=0；
对于带注释的（var i=1；i1）currentSum+=i；//，这有帮助吗

function sum(num) <-- you seem to be missing this
{ 
    var currentSum = 0;           // <-- declare variable and assign it to 0
    for (var i=1; i<= num; i++) { // <--start a loop, with i as the counter, 
                                  //    starting at 1 and finishing at whatever 
                                  //    the value of num is
        currentSum += i;    // <-- take the current value of currentSum and 
                            //     add i to it, shorthand way of writing 
                            //     currentSum = currentSum + i
    }
    //return current sum  // <-- This line is completely wrong
    return currentSum;    // <-- Return the variable currentSum after all the 
                          //       looping and summing has finished

}
//consol.long(sum(10));    // <-- this line is also wrong, there is no such 
                           //     thing as consol.long
console.log(sum(10));      // <-- should be console.log, which is outputting 
                           //     the return value of the function call sum, 
                           //     passing in a value of 10 as the input 
                           //     parameter num, to the console.
                           //     Which in most browsers, can be located via F12

函数和（num）
2*-->这里似乎有点不正确。空格不应该在那里。您正在从函数返回计算值。
这甚至不是有效的javascript。请发布一些有效的内容，至少可以运行。代码中似乎缺少函数的开头？它不应该以函数sum（num）开头吗
 return currentSum  // will return the final value.

function sum(num) <-- you seem to be missing this
{ 
    var currentSum = 0;           // <-- declare variable and assign it to 0
    for (var i=1; i<= num; i++) { // <--start a loop, with i as the counter, 
                                  //    starting at 1 and finishing at whatever 
                                  //    the value of num is
        currentSum += i;    // <-- take the current value of currentSum and 
                            //     add i to it, shorthand way of writing 
                            //     currentSum = currentSum + i
    }
    //return current sum  // <-- This line is completely wrong
    return currentSum;    // <-- Return the variable currentSum after all the 
                          //       looping and summing has finished

}
//consol.long(sum(10));    // <-- this line is also wrong, there is no such 
                           //     thing as consol.long
console.log(sum(10));      // <-- should be console.log, which is outputting 
                           //     the return value of the function call sum, 
                           //     passing in a value of 10 as the input 
                           //     parameter num, to the console.
                           //     Which in most browsers, can be located via F12

function sum(n)
{ 
    var currentSum = 0;
    for (var i=1; i<=num; i++) {
        currentSum += i; // <-- 1*
    }
    return currentSum; // <-- 2*     
}

   currentSum  = currentSum  + i