for-in循环应该用在非数组对象的遍历上,使用for-in进行循环也被称为“枚举”。 从技术上将,你可以使用for-in循环数组(因为JavaScript中数组也是对象),但这是不推荐的。因为如果数组对象已被自定义的功能增强,就可能发生逻辑错误。另外,在for-in中,属性列表的顺序(序列)是不能保证的。所以最好数组使用正常的for循...
In this final chapter on flow control, we will look at another of the shell’s looping constructs.The for loop differs from the while and until loops in that it providesa means of processing sequences during a loop. This turns out to be very useful when programming.Accordingly, the for ...
Loops in C is used to execute the block of code several times according to the condition given in the loop. It means it executes the same code multiple times so it saves code and also helps to traverse the elements of an array. There are 3 types of loops in C: while loop in C do...
在前端开发过程中,我们经常使用到JavaScript 提供了很多种循环和迭代的方法,常见for, for…of, for…in, while, Array.forEach, 以及 Array.* (还有一些 Arra...
Well, the thing is that it's very conventional and natural to begin at 0 and iterate the given number of times using the < operator, even though sometimes the 0 might not have any practical significance as in the code above. Nested loops A for loop's body can contain any valid statemen...
do…while— loops through a block of code once; then the condition is evaluated. If the condition is true, the statement is repeated as long as the specified condition is true. for— loops through a block of code until the counter reaches a specified number. for…in— loops through the ...
Learn about for...in loops in JavaScript: their syntax, how they work, when to use them, when not to use them, and what you can use instead.
JavaScript supports different kinds of loops:for - loops through a block of code a number of times for/in - loops through the properties of an object while - loops through a block of code while a specified condition is true do/while - also loops through a block of code while a ...
The break statement terminates the for loop immediately before it loops through all the items. For example, languages = ['Swift', 'Python', 'Go', 'C++'] for lang in languages: if lang == 'Go': break print(lang) Run Code Output Swift Python Here, when lang is equal to 'Go', th...
JavaScript For Loops Loopsare used in programming to automate repetitive tasks. The most basic types of loops used in JavaScript are thewhileanddo...whilestatements, which you can review in “How To Construct While and Do…While Loops in JavaScript.”...