声明
-
属于类而不是类的实例的方法
- 在类加载时就已经存在，可以通过类名直接调用，而无需实例化类
-
用于创建实用程序函数
class ClassWithStaticMethod {
static staticProperty = 'someValue';
static staticMethod() {
return 'static method has been called.';
}
}
console.log(ClassWithStaticMethod.staticProperty);
// output: "someValue"
console.log(ClassWithStaticMethod.staticMethod());
// output: "static method has been called."
调用
静态方法中调用其他静态方法需要使用this关键字
class StaticMethodCall {
static staticMethod() {
return 'Static method has been called';
}
static anotherStaticMethod() {
return this.staticMethod() + ' from another static method';
}
}
console.log(StaticMethodCall.staticMethod())
// 'Static method has been called'
console.log(StaticMethodCall.anotherStaticMethod())
// 'Static method has been called from another static method'
在非静态方法中，通过类名和this.constructor来调用
用类名来调用：CLASSNAME.STATIC_METHOD_NAME()
用构造函数的属性来调用该方法： this.constructor.STATIC_METHOD_NAME()
- 不能使用
this关键字来访问静态方法
class StaticMethodCall {
constructor() {
console.log(StaticMethodCall.staticMethod());
// 'static method has been called.'
console.log(this.constructor.staticMethod());
// 'static method has been called.'
}
static staticMethod() {
return 'static method has been called.';
}
}
