Javascript:对象不支持方法' freeze'
问题描述：
我正在尝试使用Javascript创建枚举. 使用的javascript代码是
I am trying to create an enummeration in Javascript. The javascript code used is
var FeatureName = {
"FEATURE1": 1,
"FEATURE2": 2,
"FEATURE3": 3,
"FEATURE4": 4,
"FEATURE5": 5
}
Object.freeze(FeatureName);
调用方法 Object.freeze(FeatureName)时，该方法对于除IE7和IE8以外的所有浏览器都适用.除此之外，还有其他选择吗?
When the method Object.freeze(FeatureName), is called it works fine for all the browsers except IE7 and IE8. Is there any alternative to this?
答
John Resig提供了一种替代方法.我没有在您提到的浏览器中尝试过.试试看，让我们知道.
John Resig provides an alternative. I haven't tried it in the browsers you mention. Try it and let us know.
http://ejohn.org/blog/ecmascript-5-objects -and-properties/
Object.freeze = function( obj ) {
var props = Object.getOwnPropertyNames( obj );
for ( var i = 0; i < props.length; i++ ) {
var desc = Object.getOwnPropertyDescriptor( obj, props[i] );
if ( "value" in desc ) {
desc.writable = false;
}
desc.configurable = false;
Object.defineProperty( obj, props[i], desc );
}
return Object.preventExtensions( obj );
};