I have the following problem: I have to create Veiables like such:
var qrcode_1 = my_CreateQRcode(document.getElementById("qrcode_1"));
var qrcode_2 = my_CreateQRcode(document.getElementById("qrcode_2"));
var qrcode_3 = my_CreateQRcode(document.getElementById("qrcode_3"));
.....
The number of the variables can bie fom 1 to 60.. ist it possible to create these varibles dynamically depending on the amount of actually needed variables.. of have I to degine 60 variables in the code?
You could use an array instead:
var qrcodes = Array.from(
{ length: 60 },
(_, i) => my_CreateQRcode(document.getElementById('qrcode_' + (i + 1)))
)
But it would be better to use classes instead of numeric-indexed IDs, so you could do something like
var qrcodes = Array.from(
document.querySelectorAll('.qrcode'),
my_CreateQRcode // second argument to Array.from is a mapper function
);
Note that array-like structures are zero-indexed, not one-indexed, so, for example, qrcodes[0] will correspond to the first element found and sent through .my_CreateQRcode.
If for whatever reason you really need that many variables (as others pointed out, you really should use an array instead), this is how you can achieve that:
for (let i = 60; i > 0; i--) {
window["qrcode_"+i] = my_CreateQRcode(document.getElementById("qrcode_"+i))
};
Please note that in this specific scenario this is overwriting the already existing variables (the browser automatically creates a global variable for each element with a unique id value under the name of that value, which holds a reference to that element).
You can create class for your html element.
Example:
In HTML->
<div class="qrcode"></div>....<div class="qrcode"></div>
IN JS ->
var qrcodes= document.getElementsByClassName(".qrcode");
for(i=0;i<=qrcodes.length;i++){
log(qrcodes[i]);
}
qrcodevariables but you try to useqrcode_60? That would throw an error. And if you don't know how many there are, how would you know which identifiers to use - you won't be able to determine if there are 5 or 50 of them, if you merely have an unknown amount of variables.