How to access same variable name inside function in javascript

Question

How to access same variable name inside function in javascript

var xyz = "Hello";
console.log("outside function: " + xyz)
function abc() {
    var xyz = "World!";
    console.log("inside function: " + xyz) // output should be "Hello world!"
} abc();

Answer 1

尝试：

var xyz = "Hello";
console.log("outside function: " + xyz)
function abc() {
    var xyz = (window.xyz || "") +" " + "World!";
    console.log("inside function: " + xyz) // output should be "Hello world!"
} abc();

Answer 2

如果您不想编辑xyz的值：

var xyz = "Hello";
console.log("outside function: " + xyz)
function abc() {
    var abc = " World!";
    console.log("inside function: " + xyz + abc) // output should be "Hello world!"
} abc();

如果你想编辑xyz的值：

var xyz = "Hello";
console.log("outside function: " + xyz)
function abc() {
    xyz += " World!";
    console.log("inside function: " + xyz) // output should be "Hello world!"
} abc();

Answer 3

尝试使用窗口。这将允许您访问全局声明的变量。

var xyz = window.xyz ..

Answer 4

为什么不把它作为参数传递？ 绝对不需要使用global变量。

var xyz = "Hello";
console.log("outside function: " + xyz)
function abc(xyz) {
    var xyzUpdated = xyz + "World!";
    console.log("inside function: " + xyzUpdated) // output should be "Hello world!"
} abc(xyz);