value is always empty inside ternary operator statement

Question

I am using ReactJS and a library called React-Table for an online gaming site.

In the table, I have one column cell that could potentially be empty or NULL.

So, if that column cell is null or empty or undefined, then I want to show a value called, "Dungeon Master".

If it's not null or empty, then I just want to show what should be shown(row.original.gamerTag).

So I tried using a ternary operator to check, but no matter what, the value always shows empty.

Here is where I use it:

{
    Header: 'Gamer Title',
    accessor: 'gamerTitle',
    Cell: ({ row }) =>
        <a href="#" onClick={() =>
            show(
                row.original.id,
                row.original.gamerTitle,
                row.original.gameType,
                (row.original.gamerTag == 'undefined' || '' || null) ? 'Dungeon Master' : row.original.gamerTag,
                row.original.gameDescription,
            )}>
            {row.original.gamerTitle}
        </a>
},

Am I using it wrong? I don't get any errors or anything.

Thanks!

Does this answer your question? [JavaScript: Simple way to check if variable is equal to two or more values?](https://stackoverflow.com/questions/12116326/javascript-simple-way-to-check-if-variable-is-equal-to-two-or-more-values) — Heretic Monkey, Jul 13 '20 at 15:38
In other words, that construct doesn't do what you think it does. — Heretic Monkey, Jul 13 '20 at 15:39

score 3 · Answer 1 · answered Jul 13 '20 at 15:41

Replace

(row.original.gamerTag == 'undefined' || '' || null) ? 'Dungeon Master' : row.original.gamerTag

By

typeof row.original.gamerTag === 'undefined' || row.original.gamerTag === '' || row.original.gamerTag === null ? 'Dungeon Master' : row.original.gamerTag

Two problem, the one is myVar == 'undefined' doesnt work because you compare string and not type. And secondly, in js is not short syntaxe for concat condition. Alternatively you can try [undefined, null, ''].includes(row.original.gamerTag).

macborowy · Accepted Answer · 2020-07-13T15:43:52.887

1

Try replacing:

(row.original.gamerTag == 'undefined' || '' || null) ? 'Dungeon Master' : row.original.gamerTag

with:

(row.original.gamerTag == 'undefined' || row.original.gamerTag == '' || row.original.gamerTag == null) ? 'Dungeon Master' : row.original.gamerTag

edited Jul 13 '20 at 15:43

answered Jul 13 '20 at 15:38

macborowy

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value is always empty inside ternary operator statement

2 Answers2