A JavaScript function is executed when "something" invokes it (calls it). Example // Function to compute the product of p1 and p2 functionmyFunction(p1, p2) { returnp1 * p2; } Try it Yourself » JavaScript Fu
Function Declarations Earlier in this tutorial, you learned that functions aredeclaredwith the following syntax: functionfunctionName(parameters) { code to be executed } Declared functions are not executed immediately. They are "saved for later use", and will be executed later, when they are ...
Earlier in this tutorial, you learned that functions aredeclaredwith the following syntax: functionfunctionName(parameters) { //code to be executed } Declared functions are not executed immediately. They are "saved for later use", and will be executed later, when they are invoked (called upon)...
console.log(square(5)); // 25 function square(n) { return n * n; } 尽管square() 函数在声明之前被调用,但此代码的运行并没有任何错误。这是因为 JavaScript 解释器会将整个函数声明提升到当前作用域的顶部,因此上面的代码等价于: jsCopy to Clipboard // 所有函数声明实际上都位于作用域的顶部 functi...
The syntax of thecall()method is: func.call(thisArg, arg1, ... argN) Here,funcis a function. call() Parameters Thecall()method can taketwoparameters: thisArg- ThethisArgis the object that thethisobject references inside the functionfunc. ...
Here are a few examplesof basic syntax: // Two slashes start single-linecommentsvarx;// declaring a variablex=3+y;// assigning a value to the variable `x`foo(x,y);// calling function `foo` with parameters `x` and `y`obj.bar(3);// calling method `bar` of object `obj`// A...
apply() Syntax The syntax of theapply()method is: func.apply(thisArg, argsArray) Here,funcis a function. apply() Parameters Theapply()method can taketwoparameters: thisArg- The value ofthiswhich is provided while callingfunc. argsArray(optional) - An array containing the arguments to the fu...
// Defining function `baz` with parameters `a` and `b` function baz(a, b) { return a + b; } 注意等号的两种不同用法: 单个等号(=)用于将一个值赋给一个变量。 三个等号(===)用于比较两个值(参见相等运算符)。 注释 有两种注释: ...
The first is syntax errors (covered in Code Quality). The second is unintentional side effects. Unintentional side effects are the bane of code reuse. They occur when multiple functions depend on and manipulate the values of the same variables or object properties. In this situation, it becomes...
@Functions emulate their counterparts in Notes®. The syntax differs as follows: Names must be in exact case. Parameters are separated by commas not semicolons.@Abs (JavaScript) Returns the absolute (unsigned) value of a number. @Abstract (JavaScript) Abbreviates the content of fields. @...