function getTwoVariables() { var variable1 = "Value 1"; var variable2 = "Value 2"; return { variable1: variable1, variable2: variable2 }; } var result = getTwoVariables(); console.log(result.variable1); // 输出: Value 1 console.log(result.variable2); // 输出: Value 2 在这个...
lastName){ greetingMsg = greetingMsg + firstName + " " + lastName; } return { sendGreeting: function(firstName, lastName){ msgTo(firstName, lastName); } getMsg: function(){ return greetingMsg; } } } const createMsg = sayHello(); createMsg.send...
return x * x; // Compute the function's value }; // Semicolon marks the end of the assignment. square(plus1(y)) // => 16: invoke two functions in one expression 在ES6 及更高版本中,有一种用于定义函数的简洁语法。这种简洁语法使用=>将参数列表与函数体分开,因此用这种方式定义的函数被称...
When adding two variables, it can be difficult to anticipate the result: letx =10; lety =5; letz = x + y;// Now z is 15 letx =10; lety ="5"; letz = x + y;// Now z is "105" Try it Yourself » Misunderstanding Floats ...
varFile=function(){// open IIFEvarUNTITLED='Untitled';functionFile(name){this.name=name||UNTITLED;}returnFile;}();// close IIFE In the preceding example, there are two different variables that have the nameFile. On one hand, there is the function that is only directly accessible inside th...
The most important predicates involving variables, their declarations, and their accesses are as follows: Variable.getName(), VarDecl.getName(), VarAccess.getName() return the name of the variable. Variable.getScope() returns the scope to which the variable belongs. Variable.isGlobal(), Variabl...
Allglobalvariables Objects are kept in memory at least as long as they are accessible from any of the roots through a reference or a chain of references. There is a garbage collector in the browser that cleans memory occupied by unreachable objects; in other words, objects will be removed fr...
() converts variables to numbersThe global method Number() can even convert dates to numbersThe global method parseInt() converts strings to numbersThe global method parseFloat() converts strings to numbersMAX_VALUE returns the largest possible number in JavaScriptMIN_VALUE returns the smallest ...
variables are properties of a global objectand that local variables are properties of a special call object, we can return to the notion of variable scope and reconceptualize it. This new description of scope offers a useful way to think about variables in many contexts; it provides a powerful...
Profile variables give expressions access to data values connected to a layer, map, or workspace. These values are the inputs to the expression, required for producing a valid return value as defined by the expression author. For example $feature provides expressions access to a feature's ...