访问JavaScript对象变量属性

Not all JavaScript objects are as easy as MyObject.property. Sometimes you may want to access a property whose key is stored in a variable. Luckily accessing these properties is very easy.

并非所有JavaScript对象都像MyObject.property一样容易。 有时您可能想访问其键存储在变量中的属性。 幸运的是，访问这些属性非常容易。

Javascript对象属性访问示例 (Javascript Object Property Accessing Example)

/* setting */ var myObject = { left : 30, top: 20 }; /* basic access */ var left = myObject.left; //OR var left = myObject['left']; /* accessing it or variables */ var mode = 'vertical'; var value = myObject[mode == 'horizontal' ? 'left' : 'top'];

You may use array-style syntax to access an object's properties. The string within brackets returns the properties.

您可以使用数组样式的语法来访问对象的属性。 方括号中的字符串返回属性。

翻译自: https://davidwalsh.name/access-object-properties