arrays - Javascript unbind variables -


this question has answer here:

i have following code copy variable value change value.

var = [{name: 'john doe'}];  var b = a;    document.write(b[0].name + '<br />');  document.write(a[0].name + '<br /><br />');    b[0].name = 'jane doe';    document.write(b[0].name + '<br />');  document.write(a[0].name + '<br />');

but somehow change first variable value

how make variable keep value?

you assigning a-reference b. may want copying array changes a not reflected b. see this thread different assignments in javascript.

take @ fastest way duplicate array. it's speed of different array copy methods. quick answer is:

var b = a.slice();

the slice() method creates new array same elements original one. careful it's shallow copy.

you use json.stringify() , json.parse()methods doing deep copy.


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