What is the best way to test for an empty string with jquery-out-of-the-box

Question

What is the best way to test for an empty string with jquery-out-of-the-box  i e  without plugins  I tried this    But it did t work at least out-of-the-box  It would be nice to use something that s builtin   I wouldn t like to repeat   if  a    null    a        everywhere if some  if  isempty a     would be available

User · Answer

if  a trim          a        a  null           empty condition   else         working condition

User · Answer

The link you gave seems to be attempting something different to the test you are trying to avoid repeating   if  a    null    a        tests if the string is an empty string or null  The article you linked to tests if the string consists entirely of whitespace  or is empty    The test you described can be replaced by   if   a    Because in javascript  an empty string  and null  both evaluate to false in a boolean context

User · Answer

if  my string       stuff      and  if my string           if you want to accept null but reject empty  EDIT  woops  forgot your condition is if it IS empty

User · Answer

Check if data is a empty string  and ignore any white space  with jQuery   function isBlank  data         return     trim data  length    0

User · Answer

To checks for all  empties  like null  undefined                    var isEmpty   function data        if typeof data       object            if JSON stringify data              JSON stringify data                         return true           else if  data               return true                    return false       else if typeof data       string            if  data trim                 return true                    return false       else if typeof data       undefined            return true       else          return false            Use cases and results   console log isEmpty        true console log isEmpty null       true console log isEmpty          true console log isEmpty            true console log isEmpty undefined       true console log isEmpty          true console log isEmpty          true console log isEmpty 0       false console log isEmpty  Hey        false

User · Answer

Try this  if  a    a length     0

User · Answer

Based on David s answer I personally like to check the given object first if it is a string at all  Otherwise calling  trim   on a not existing object would throw an exception   function isEmpty value      return typeof value     string   amp  amp   value trim      typeof value     undefined     value     null      Usage   isEmpty undefined      true isEmpty null      true isEmpty         true isEmpty  foo       false isEmpty 1      false isEmpty 0      false

User · Answer

if   a         is emtpy     To ignore white space for strings   if   a trim             is empty or whitespace     If you need legacy support  IE8-  for trim    use   trim or a polyfill

User · Answer

Since you can also input numbers as well as fixed type strings  the answer should actually be   function isBlank value      return   trim value

User · Answer

Try executing this in your browser console or in a node js repl   var string        string   true   false    - gt  true  string       string   true   false    - gt  false   Therefore  a simple branching construct will suffice for the test   if string           string is not empty

[javascript] What is the best way to test for an empty string with jquery-out-of-the-box?

Examples related to javascript

Examples related to jquery