What is the best way to verify both a null value and a length simultaneously within a template condition?

There is a data that can be null or an empty array, but the template should still be rendered if leaseApDto is not null or has a length greater than 0.

I attempted to use the condition 

model.leaseApDto !== null || model.leaseApDto.length !=== 0
, but they do not seem to work together even though it is an OR condition.

Any suggestions? Your help would be greatly appreciated. Thank you.

leaseApDto with a null value

https://i.stack.imgur.com/IdpFQ.png

leaseApDto with an empty value but still an array

https://i.stack.imgur.com/mDbEE.png

#code

  <div *ngIf="model.leaseApDto !== null || model.leaseApDto.length !=== 0" class="transaction-lease-details-list">
        <div class="description-header">
        </div>
        <div>
            <div class="transaction-lease-details-content list-row-divider">
                <div class="transaction-lease-details-left-label">
                    Current Base Rent (Annual)
                </div>
angulartypescript

Answer №1

Have you considered using && instead of || in your situation?

Alternatively, you could opt for a more concise solution:

*ngIf="model.leaseApDto?.length"

The ? operator is a safe navigation tool that can greatly streamline your code and be particularly useful in scenarios like this.

In my opinion, it's wise to include a check for model as well, such as 

*ngIf="model?.leaseApDto?.length"

Answer №2

Make sure that the model.leaseApDto is not null and its length is greater than zero.

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