if statement - Using ifelse to define const in Javascript - Stack Overflow

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I'm using const in a function to define a few variables as follows

const printBlock.format({
  name : this.matchedData.clientName,
  date : this.matchedData.jobDate,
  destination : this.matchedData.address,
  apartment : this.matchedData.address2,
  stateZip : this.matchedData.zipcode
})

From then, I'm printing out all of these things in order that they're declared. However, some of the data doesn't have an apartment number so it'll show up as:

John Doe

6/6/2018

135 Testdemo Avenue

null

NY 11111

Is it possible to use an if function within declaring the consts in order to make it so that:

if (this.matchedData.address2 == null){
//Do nothing
} else {
apartment : this.matchedData.address2,
}

I'm using const in a function to define a few variables as follows

const printBlock.format({
  name : this.matchedData.clientName,
  date : this.matchedData.jobDate,
  destination : this.matchedData.address,
  apartment : this.matchedData.address2,
  stateZip : this.matchedData.zipcode
})

From then, I'm printing out all of these things in order that they're declared. However, some of the data doesn't have an apartment number so it'll show up as:

John Doe

6/6/2018

135 Testdemo Avenue

null

NY 11111

Is it possible to use an if function within declaring the consts in order to make it so that:

if (this.matchedData.address2 == null){
//Do nothing
} else {
apartment : this.matchedData.address2,
}

• javascript
• if-statement
• constants

Share Improve this question Follow edited Jun 6, 2018 at 20:51 Keyadun asked Jun 6, 2018 at 19:45 KeyadunKeyadun 91511 gold badge1010 silver badges1515 bronze badges 1

• 5 const printBlock({…}) is a syntax error. What are you actually doing? – Bergi Commented Jun 6, 2018 at 19:50

Add a ment  | 

4 Answers 4

Sorted by: Reset to default 3

No, but you can use a ternary

var object = {
  address: '1111',
  apartment : this.matchedData.address2 ? "" : this.matchedData.address2
}

You could use Object.assign and check with property and if not null, take an object for assignment.

printBlock(Object.assign(
    {
        name: this.matchedData.clientName,
        date: this.matchedData.jobDate,
        destination: this.matchedData.address,
        apartment: this.matchedData.address2,
        stateZip: this.matchedData.zipcode
    }, 
    this.matchedData.address2 === null || { apartment: this.matchedData.address2 }    
));

You can create your object first without the apartment entry and then add the apartment entry if it is not null...

const a = {
  name : this.matchedData.clientName,
  date : this.matchedData.jobDate,
  destination : this.matchedData.address,
  stateZip : this.matchedData.zipcode
};

if (this.matchedData.address2 !== null){
  a.apartment : this.matchedData.address2;
}

const printBlock({...}) will throw an error because it isn't a valid way to initialize a constant. If printBlock is a function, why not handle null values in the body of printBlock?

function printBlock(obj) {
    for (var prop in obj) {
        if (obj[prop]) {
            console.log(obj[prop]); // or do whatever you mean by 'print'
        }
    }
}

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