how to make 2d array in function global

Question

i have make a web code, which i want to create a global 2d array, but that array seems like not global, may any one please give me some hints on how to make that happen, thx

for the code, please see my shared codes, it is the only public code that i have

Answer 1

Check my answer on this thread:

https://www.sololearn.com/discuss/671863/?ref=app

It could help you to understand how closure (and scope of variables) works ^^

Answer 2

That's because you declared the array within a function.

Answer 3

but i must do that, because i need to call it for each tr, is there a method that i could make it global?

Answer 4

No you mustn't do that, you can declare it outside of the function then append values in it everytime the button is clicked

Answer 5

Declare it outside the function and set it inside the function. You also have several HTML errors.

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="container">
<table>
<tr id="row1" onclick="find(this)">
<td>foo1</td>
<td>bar1</td>
<td class="hidden"></td> <!-- hidden is a class -->
</tr>
<tr id="row2" onclick="find(this)">
<td>foo2</td>
<td>bar2</td>
</tr>
<tr id="row3" onclick="find(this)">
<td>foo2</td>
<td>bar2</td>
</tr>
</table>
<input type="textbox" id="row" placeholder="row"> <!-- input tags are self closing -->
<input type="textbox" id="col" placeholder="column"> <!-- input tags are self closing -->
<button onClick="btn()">click me</button> <!-- there isn't a button function yet -->
</div> <!-- You forgot your closing div tag -->
<script>
var td_sum; // declared outside of function to make global
function find(element){
var tr_sum = element.parentNode.childElementCount;
//count tr total
var ntr = element.id.substr(3);
//get sequence of selected row
alert(tr_sum);
td_sum = new Array(tr_sum); // set inside function
td_sum[ntr] = element.childElementCount;
//count td in selected row
alert(td_sum[ntr])
}
$('#row2').click()
</script>

Answer 6

well, i have changed the code, i now have a array
content[row][col], in this case, what should i declare outside the function? content[] or content[][]?

Answer 7

You need to declare the name outside, and you can assign value anywhere:

var myVar;

myFunction() {
myVar = new Array();
myVar[0] = new Array();
/* ... */
}

You can even write it shorter:

myVar = [];
myVar[0] = [];

And also, you can test if the variable is already defined (to not overwrite it):

if (myVar===undefined) {
myVar = ...
}