如何使用默认值从Object获取值 [英] How to get value from Object, with default value
问题描述
我经常发现自己将配置值传递给访问它们的函数,如下所示:
I constantly find myself passing config values to functions accessing them like this:
var arg1 = 'test1';
if(isUndefined(config.args.arg1)){
arg1 = config.args.arg1;
}
var arg2 = 'param2';
if(isUndefined(config.args.arg2)){
arg2 = config.args.arg2;
}
var arg3 = '123';
if(isUndefined(config.args.arg3)){
arg3 = config.args.arg3;
}
我稍后会像这样使用它们:
where I later use them like this:
var url = '<some-url>?id='+arg1+'&='+arg2 +'=' + arg3;
jQuery / ExtJS或任何其他框架是否以简单的方式提供了这样的访问变量的解决方案,并给变量一个默认值?
Does jQuery/ExtJS or any other framework provide a solution to access variables like this in a simple way, and give variables a default value?
类似于:
getValueOfObject(config,'args.arg3','<default>');
或者是否有标准的解决方案。
Or is there maybe a standard solution for this.
注意:
我也在考虑你有默认值的常见模式
I was also thinking about the common pattern where you have defaults
var defaults = {
args: {
args1: ....
}
...
}
并进行对象合并。
然后将对象编码为param String。但正如您所见,对象值有时也包含参数名称。
And then encoding the object to a param String. But as you can see the object values also sometimes contain parameter names.
推荐答案
看起来像是< _.get()的功能!
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