How to stringify an object in Javascript: converting an object to a padded & well-formatted string or simply inline

I wrote a function to convert an object in a string (stringification) without using a JSON library; you can convert an object to a well formatted string with padding or simply to an unique line:

[sourcecode language=”javascript”] function stringify(object, padding, margin){
var o = (typeof object == ‘object’ || typeof object == ‘function’) && object != null ? object : null;
var p = typeof padding == ‘boolean’ && padding ? true : false;
var m = typeof margin == ‘number’ && margin>0 && p ? margin : 0;
if(o != null){
var s = ”;
var a = function(o){return (typeof o === ‘object’ && o ? ((typeof o.length === ‘number’ &&!(o.propertyIsEnumerable(‘length’)) && typeof o.splice === ‘function’) ? true : false) : false);}; //is array?
for(var v in o){
s += typeof o[v] === ‘object’ ? (o[v] ? (
(typeof o[v].length === ‘number’ && !(o[v].propertyIsEnumerable(‘length’)) && typeof o[v].splice === ‘function’) ?
(m>0 ? Array(m).join(‘ ‘):”) + v + ‘:’ + (p ? ‘ ‘:”) + ‘[‘ + (p ? ‘rn’:”) + stringify(o[v],p,(m>0?m:1)+v.length+4) + (p!=true ? ” : ‘rn’ + Array((m>0?m:1)+v.length+2).join(‘ ‘)) + ‘],’ + (p ? ‘rn’:”) :
(m>0 ? Array(m).join(‘ ‘):”) + v + ‘:’ + (p ? ‘ ‘:”) + ‘{‘ + (p ? ‘rn’:”) + stringify(o[v],p,(m>0?m:1)+v.length+4) + (p!=true ? ” : ‘rn’ + Array((m>0?m:1)+v.length+2).join(‘ ‘)) + ‘},’ + (p ? ‘rn’:”)
) : (m>0 ? Array(m).join(‘ ‘):”) + v + ‘:’ + (p ? ‘ ‘:”) + o[v] + ‘,’ + (p ? ‘rn’:”))
: (m>0 ? Array(m).join(‘ ‘):”) + v + ‘:’ + (p ? ‘ ‘:”) + (typeof o[v] == ‘string’ ? ”’ + o[v].replace(/’/g,’\”) + ”’ : o[v]) + ‘,’ + (p ? ‘rn’:”);
};
o = s.length>0 && p!=true ? s.substring(0, s.length-1) : (s.length>2 ? s.substring(0, s.length-3) : s);
}else{
o = object;
};
return o;
};
[/sourcecode]

a little example, you declare same variable….

[sourcecode language=”javascript”] var associative_array = new Array();
associative_array[‘one’] = 1;
associative_array[‘two’] = 2;
associative_array[‘undefinedvar’];

var myobject = {
mystring: ‘value’,
myquoted: ‘string with ‘single quotation mark”,
mynumber: 1,
myboolean: true,
myarray: [1, 2, 3],
myassocarray: associative_array,
myobject: {
obj_string: ‘hi!’,
obj_number: 1,
obj_array: [
‘just’, ‘a’, ‘test’, 1, false,
[‘array’, ‘inside’, ‘array’],
{
object: ‘inside array’,
array: [1,2,3,4,5,6,7,8,9] },

] },
mynullvalue: null,
myundefined: associative_array[‘undefinedvar’],
myfunction: function(){ var s = ‘hello!’; return s; }
};
[/sourcecode]

then, for an inline stringification, you can use

[sourcecode language=”javascript”] var str = stringify(myobject);
[/sourcecode]

and “str” value will be a string as

[sourcecode language=”javascript”] mystring:’value’,myquoted:’string with ‘single quotation mark”,mynumber:1,myboolean:true,myarray:[0:1,1:2,2:3],myassocarray:[one:1,two:2],myobject:{obj_string:’hi!’,obj_number:1,obj_array:[0:’just’,1:’a’,2:’test’,3:1,4:false,5:[0:’array’,1:’inside’,2:’array’],6:{object:’inside array’,array:[0:1,1:2,2:3,3:4,4:5,5:6,6:7,7:8,8:9]}]},mynullvalue:null,myundefined:undefined,myfunction:function () {
var s = "hello!";
return s;
}
[/sourcecode]

Instead, for a stringification with a well formatted padding, you can use

[sourcecode language=”javascript”] var str_formatted = stringify(myobject, true);
[/sourcecode]

and this is the “str_formatted” value:

[sourcecode language=”javascript”] mystring: ‘value’,
myquoted: ‘string with ‘single quotation mark”,
mynumber: 1,
myboolean: true,
myarray: [
0: 1,
1: 2,
2: 3
],
myassocarray: [
one: 1,
two: 2
],
myobject: {
obj_string: ‘hi!’,
obj_number: 1,
obj_array: [
0: ‘just’,
1: ‘a’,
2: ‘test’,
3: 1,
4: false,
5: [
0: ‘array’,
1: ‘inside’,
2: ‘array’
],
6: {
object: ‘inside array’,
array: [
0: 1,
1: 2,
2: 3,
3: 4,
4: 5,
5: 6,
6: 7,
7: 8,
8: 9
] }
] },
mynullvalue: null,
myundefined: undefined,
myfunction: function () {
var s = "hello!";
return s;
}
[/sourcecode]

Finally, when you pass a variable to stringify() that is not an object, it will just return the value.

Happy stringifications!

Max 🙂