How to Convert Boolean to String

Question

I have a Boolean variable which I want to convert to a string    res   true    I need the converted value to be of the format   true   false   not  0   1    converted res    true    converted res    false     I ve tried    converted res   string  res    converted res   String  res     But it tells me that string and String are not recognized functions  How do I convert this Boolean to a string in the format of  true  or  false  in PHP

User · Answer

The other solutions here all have caveats (though they address the question at hand). If you are (1) looping over mixed-types or (2) want a generic solution that you can export as a function or include in your utilities, none of the other solutions here will work.

The simplest and most self-explanatory solution is:

// simplest, most-readable
if (is_bool($res) {
    $res = $res ? 'true' : 'false';
}

// same as above but written more tersely
$res = is_bool($res) ? ($res ? 'true' : 'false') : $res;

// Terser still, but completely unnecessary  function call and must be
// commented due to poor readability. What is var_export? What is its
// second arg? Why are we exporting stuff?
$res = is_bool($res) ? var_export($res, 1) : $res;

But most developers reading your code will require a trip to http://php.net/var_export to understand what the var_export does and what the second param is.

1. `var_export`

Works for boolean input but converts everything else to a string as well.

// OK
var_export(false, 1); // 'false'
// OK
var_export(true, 1);  // 'true'
// NOT OK
var_export('', 1);  // '\'\''
// NOT OK
var_export(1, 1);  // '1'

2. `($res) ? 'true' : 'false';`

Works for boolean input but converts everything else (ints, strings) to true/false.

// OK
true ? 'true' : 'false' // 'true'
// OK
false ? 'true' : 'false' // 'false'
// NOT OK
'' ? 'true' : 'false' // 'false'
// NOT OK
0 ? 'true' : 'false' // 'false'

3. `json_encode()`

Same issues as var_export and probably worse since json_encode cannot know if the string true was intended a string or a boolean.

User · Answer

I m not a fan of the accepted answer as it converts anything which evaluates to false to  false  no just boolean and vis-versa     Anyway here s my O T T answer  it uses the var export function   var export works with all variable types except resource  I have created a function which will perform a regular cast to string   string    a strict cast  var export  and a type check  depending on the arguments provided     if  function exists  to string          function to string  var   strict   false   expectedtype   null            if  func num args                 return trigger error   FUNCTION         expects at least 1 parameter  0 given   E USER WARNING                     if  expectedtype     null   amp  amp  gettype  var       expectedtype               return trigger error   FUNCTION         expects parameter 1 to be      expectedtype         gettype  var      given   E USER WARNING                     if is string  var                return  var                    if  strict  amp  amp   is resource  var                return var export  var  true                     return  string   var           if  function exists  bool to string          function bool to string  var           return func num args     to string  var  true   boolean     to string                     if  function exists  object to string          function object to string  var           return func num args     to string  var  true   object     to string                     if  function exists  array to string          function array to string  var           return func num args     to string  var  true   array     to string

User · Answer

Another way to do   json encode  booleanValue     echo json encode true       string  true   echo json encode false      string  false      null     false echo json encode null       string  null

User · Answer

For me  I wanted a string representation unless it was null  in which case I wanted it to remain null   The problem with var export is it converts null to a string  NULL  and it also converts an empty string to       which is undesirable  There was no easy solution that I could find   This was the code I finally used   if  is bool  val    val    val    true     val    false   else if   val     null   val    string  val    Short and simple and easy to throw in a function too if you prefer

User · Answer

You use strval   or  string  to convert to string in PHP  However  that does not convert boolean into the actual spelling of  true  or  false  so you must do that by yourself  Here s an example function   function strbool  value        return  value    true     false     echo strbool false       false  echo strbool true       true

User · Answer

Why just don t do like this    if   res         converted res    true     else        converted res    false

User · Answer

Simplest solution    converted res    res    true     false

User · Answer

The function var export returns a string representation of a variable  so you could do this   var export  res  true     The second argument tells the function to return the string instead of echoing it

User · Answer

converted res   isset    res        res    true     false       false

User · Answer

boolval   works for complicated tables where declaring variables and adding loops and filters do not work  Example    result  row  name       lt  td gt  lt td gt      boolval  row  special case       True     False       lt  td gt  lt td gt      row  more fields      tmp   where  tmp is a key used in order to transpose other data  Here  I wanted the table to display  Yes  for 1 and nothing for 0  so used  boolval  row  special case       Yes

User · Answer

See var export

User · Answer

This works also for any kind of value    a   true   echo  a                        outputs    1 echo value To String   a       outputs    true   code   function valueToString   value         return    is bool   value       value     value    true     false

User · Answer

Edited based on  sebastian-norr suggestion pointing out that the  bool variable may or may not be a true 0 or 1  For example  2 resolves to true when running it through a Boolean test in PHP   As a solution  I have used type casting to ensure that we convert  bool to 0 or 1  But I have to admit that the simple expression  bool    true     false  is way cleaner     My solution used below should never be used  LOL  Here is why not     To avoid repetition  the array containing the string representation of the Boolean can be stored in a constant that can be made available throughout the application      Make this constant available everywhere in the application const BOOLEANS     true    false      bool   true  echo BOOLEANS  bool    bool       true  echo BOOLEANS  bool    bool       false

User · Answer

Just wanted to update  in PHP    5 50 you can do boolval   to do the same thing  Reference Here

User · Answer

function ToStr  Val null  T 0        return is string  Val    Val                      is numeric  Val    T   Val   Val                                  is null  Val   NULL                                              is bool  Val    Val  TRUE   FALSE                                                           is array  Val   StrArr  Val  T                                            false                                                     function StrArr  Arr  T 0         Str          i -1      if is array  Arr       foreach  Arr AS  K   gt   V       Str       i       null   is string  K      K     K      gt     is string  V      V     ToStr  V  T 1        return  array      i  ToStr  Arr   Str         T null           A   array 1 2 array  a   gt  b   array  a   b   c   true false ToStr 100    echo StrArr  A      OR ToStr  A     OR ToStr true     OR StrArr true

[php] How to Convert Boolean to String

1. `var_export`

2. `($res) ? 'true' : 'false';`

3. `json_encode()`

Examples related to php

Examples related to string

[php] How to Convert Boolean to String

1. var_export

2. ($res) ? 'true' : 'false';

3. json_encode()

Examples related to php

Examples related to string

1. `var_export`

2. `($res) ? 'true' : 'false';`

3. `json_encode()`