Memory Usage Of Different Data Types in javascript -

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a question has happened me different data type in javascript how many use of memory . example in c++ data type int , char , float uses order 2 , 1 , 8 byte of memory . data type number , string , boolean , null , undefind , objects , arrays in javascript how many use of memory , ranges accepted ? accept apologize because of low english level!!!

numbers 8 bytes.

found in w3schools page.

i searched around bit more other javascript primitive types, it's surprisingly hard find information! did find following code though:

    ...     if ( typeof value === 'boolean' ) {         bytes += 4;     }     else if ( typeof value === 'string' ) {         bytes += value.length * 2;     }     else if ( typeof value === 'number' ) {         bytes += 8;     }     ...

seems indicate string 2 bytes per character, , boolean 4 bytes.

found code here , here. full code's used rough size of object.

although, upon further reading, found interesting code konijn on page: count byte length of string.

function getbytecount( s ) {   var count = 0, stringlength = s.length, i;   s = string( s || "" );   for( = 0 ; < stringlength ; i++ )   {     var partcount = encodeuri( s[i] ).split("%").length;     count += partcount==1?1:partcount-1;   }   return count; } getbytecount("i♥js"); // 6 bytes getbytecount("abcd"); // 4 bytes

so seems string's size in memory depends on characters themselves. although still trying figure out why set count 1 if it's 1, otherwise took count-1 (in loop).

will update post if find else.


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