是的,就像其他人说的,你可以用var在全局范围(所有函数之外)声明一个全局变量:var yourGlobalVariable;function foo() { // ...}或者,您可以将属性分配给window:function foo() { window.yourGlobalVariable = ...
However, avoid using the global scope and wrap your code in a scoping function and use local variables to that scoping function, and make your other functions closures within it like this:Javascript global variable1 2 3 4 5 6 7 (function () { // Begin scoping function let yourGlobal...
Each global is given a value oftrueorfalse. A value oftrueindicates that the variable may be overwritten. A value offalseindicates that the variable should be considered read-only. This information is used by static analysis tools to flag incorrect behavior. We assume all variables should befal...
// bad (function example() { // JavaScript interprets this as // let a = ( b = ( c = 1 ) ); // The let keyword only applies to variable a; variables b and c become // global variables. let a = b = c = 1; }()); console.log(a); // throws ReferenceError console.log...
JavaScript was designed to be easy to learn and allows the developer to make certain mistakes. For example, JavaScript doesn't throw an error when you use a misspelled variable, and instead creates a new global one. When you start learning JavaScript, having fewer errors is convenient. However...
Variable declarations - Choose one of the following options to configure alignment for equality signs: Do not align: the equality signs are not aligned. Align when multiline: the equality signs in multiline var statements are aligned by inserting additional spaces. Align when grouped: the equality...
First, we create an output variable to contain all the HTML output, including questions and answer choices.Next, we can start building the HTML for each question. We’ll need to loop through each question like this:myQuestions.forEach( (currentQuestion, questionNumber) => { // the code ...
When you’re a variable, you work hard and life can be short. That is, unless you’re a global variable, but even with globals, life has its limits. But what determines the life of a variable? Think about it like this: Globals live as long as the page. A global variable begins li...
global variable leaks [boolean] --delay Delay initial execution of root suite [boolean] --exit Force Mocha to quit after tests complete [boolean] --forbid-only Fail if exclusive test(s) encountered [boolean] --forbid-pending Fail if pending test(s) encountered [boolean] --global, --...
Although we do have access to all the data in the allPlayerStatLines variable, we can do a little upfront work to make it easier to access only the data we really need: player name and PER for each of the four quarters. To get this data, we'll create a map of player names to ...