properties - How to create an object property from a variable value in JavaScript? -

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• how add property javascript object using variable name? 8 answers

i want add new property 'myobj', name 'string1' , give value of 'string2', when it returns 'undefined:

var myobj = new object; var = 'string1'; var b = 'string2'; myobj.a = b;  alert(myobj.string1); //returns 'undefined' alert(myobj.a); //returns 'string2' 

in other words: how create object property , give name stored in variable, not name of variable itself?

there's the dot notation , bracket notation

myobj[a] = b;