具有可选参数的JavaScript函数 [英] JavaScript function with optional parameters

问题描述

我是来自Python背景的JavaScript新手。在Python中，参数可以这样作为键和值传递：

I'm new to JavaScript coming from Python background. In Python parameters can be passed as key and value as such:

def printinfo( name, age = 35 ):
   print "Name: ", name
   print "Age ", age
   return;

然后可以这样调用该函数：

Then the function could be called as such:

printinfo( age=50, name="miki" )
printinfo( name="miki" )

可以在JavaScript函数中传递这样的参数吗？

Can such parameters be passing in JavaScript functions?

我希望能够传递一个或多个参数。例如这样的JavaScript函数：

I want to be able to pass one or more parameter. For example a JavaScript function as such:

function plotChart(data, xlabel, ylabel, chart_type="l"){
    ...
} 

我想只传递数据和图表类型和标签是可选的，例如：

I want to be able to pass only data and chart type and labels are optional such as :

plotChart(data, chart_type="pie")

JavaScript是否可能？

Is this possible with JavaScript?

推荐答案

<一个很好的方法是对所有参数使用一个对象。

A good way to do this would be to use an object for all of the arguments. Something like:

function plotChart(options) {
  // Set defaults
  options.chart_type = options.chart_type || '1';

  // Check if each required option is set
  // Whatever is used by the data
}

然后在调用函数时：

plotChart({
  data: 'some data',
  xlabel: 'some xlabel',
  ylabel: 'some ylabel',
  chart_type: '5' // This is optional
});

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