javascript - 仅使用var在JavaScript中声明一个布尔值(Declaring a boolean in JavaScript using just var)

Question

If I declare a JavaScript boolean variable like this:(如果我声明一个像这样的JavaScript布尔变量：)

var IsLoggedIn; And then initialize it with either true or 1 , is that safe?(然后用true或1初始化它，这样安全吗？) Or will initializing it with 1 make the variable a number?(或者用1初始化它使变量成为一个数字？)   ask by mrblah translate from so

Answer 1

Types are dependent to your initialization:(类型取决于您的初始化：)

var IsLoggedIn1 = "true"; //string var IsLoggedIn2 = 1; //integer var IsLoggedIn3 = true; //bool But take a look at this example:(但是看看这个例子：) var IsLoggedIn1 = "true"; //string IsLoggedIn1 = true; //now your variable is a boolean Your variables' type depends on the assigned value in JavaScript.(变量的类型取决于JavaScript中的赋值。)