ejs and null

[Angelo Chen]

hi,

using ejs in expressjs app, if a property of json is null, used in a
form like following, the field shows 'null', is there a way not
showing as 'null' but just a blank?

<input type="text" name="photo[remark]" value="<%=photo.remark%>" />

thanks,

angelo

[Dmitriy Petrov]

Hi,

I think You can use this

<input type="text" name="photo[remark]" value="<%=photo.remark || ''%>" />

[Angelo Chen]

Hi,

very clever! but why it works? || is logical operator of js, can not
figure out why.

angelo

[Dmitriy Petrov]

Hi,

You can use javascript between <% %>, thats why it works
http://nodejs.org/docs/latest/api/vm.html

[Pablo Botelho]

but why the logical operator OR prevents the 'null'  text from being shown?

2012/2/9 Dmitriy Petrov <i.am....@gmail.com>

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[Paul Vencill]

Because of how JavaScript logic works.  A null interprets as a logical 'false' also, so you can use || as a null coalescing operator as well as a boolean operator.  It's common to do things like:

function my_func(options){

    options = options || {};  // where {} might also be the default options

 /*... more code .. */

}

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[Pablo Botelho]

thank you very much!

2012/2/9 Paul Vencill <paul.v...@gmail.com>