Conditional Statement in JavaScript Object

Question

I have the following Dygraph object being created:

function prime() {
  g = new Dygraph(
    document.getElementById("g"),
      data, //This is the variable I want to avoid passing in for older browsers
      {
      labelsDivStyles: { 'textAlign': 'right' },
      title: document.getElementById("title").value,
      titleHeight: 35,
      labelsSeparateLines: true,
      includeZero: true
      }
  );
}

And I want to have a browser check that determines whether to include the "data" such as:

if(Browser.Version() > 8){
  //include data variable
} else{
  //don't include
}

Does anyone have any ideas outside of creating a second function to deal with the other case

Answer 1

You either need to create and manipulate the object literal beforehand, or you need to alternate with a ternary operator between value and null / undefined .

var myObj = {
    labelsDivStyles: { 'textAlign': 'right' },
    title: document.getElementById("title").value,
    titleHeight: 35,
    labelsSeparateLines: true,
    includeZero: true
};

if( Browser.Version() > 8 ) {
    myObj.data = 42;
}

or

function prime() {
    g = new Dygraph(
     document.getElementById("g"),
      data,
      {
      labelsDivStyles: { 'textAlign': 'right' },
      title: document.getElementById("title").value,
      titleHeight: 35,
      labelsSeparateLines: true,
      includeZero: true,
      data: Browser.Version() > 8 ? 42 : null
      }
  );
}

You might also choose to have a self-invoking function which does the job and returns that object, but thats pretty much the same as example #1. Either way, you can't tell ECMAscript to create or to not-create a key while forming an object literal.