I'm beginner in javascript and I have a problem to convert a string to a array of int. I find for this case
var string = "[1,2,3,4]";
but not for this one:
var string = "[[1,2],[1,2]]";
And have the same syntax
var result = [[1,2],[1,2]];
result = [[1,2],[1,2]];
Try this:
var
str = '[[1,2],[3,4]]',
result;
result = JSON.parse(str);
result[0] // [1, 2]
result[1] // [3, 4]
result[0][0] // 1
result[1][1] // 4
I don't recommend you to use eval() function.
Object-Oriented JavaScript - Second Edition: eval() can be useful sometimes, but should be avoided if there are other options. Most of the time there are alternatives, and in most cases the alternatives are more elegant and easier to write and maintain. "Eval is evil" is a mantra you can often hear from seasoned JavaScript programmers. The drawbacks of using eval() are:
Security – JavaScript is powerful, which also means it can cause damage. If you don't trust the source of the input you pass to eval(), just don't use it.
Performance – It's slower to evaluate "live" code than to have the code directly in the script.
JSON.parseshould handle both. Perhaps the question could be clearer. What is your expected output forvar string = "[1,2,3,4]";JSON.parsewill convert that to the expected output.eval("[[1,2],[1,2]]")evalunless you have to dynamically write actual javascript code. Using it to parse JSON data is unsafe and highly discouraged.