Dynamic, multidimensional array in javascript - counting up not working-CodePudding

I need a 3 dimensional array to count up - it needs to grow dynamically. It consists of index, string1 and string2.

This outputs exactly, what I want (for a single loop, since the array is just hardcoded to index 0)

   var otr_entries=[[0,"",""]];
   var otr_entries_count=0;

   some_working_for_loop()
   {
      if(is_important_value_to_save())
      {
         //otr_entries_count=otr_entries_count 1;
         otr_entries[otr_entries_count][1]=xx[i].previousElementSibling.innerHTML;
         otr_entries[otr_entries_count][2]=xx[i].innerHTML;
         window.alert(otr_entries[otr_entries_count][1]); // Expected output
         window.alert(otr_entries[otr_entries_count][2]); // Expected output
      }
   }

but when I replace otr_entries[0][2] with otr_entries[otr_entries_count][2] the script suddenly fails, if the count is not 0. That means, that the array is not just growing. So how can this be archived?

   var otr_entries=[[0,"",""]];
   var otr_entries_count=0;

   just_some_perfectly_working_for_loop(;;)
   {
      if(is_important_value_to_save())
      {
         otr_entries_count=otr_entries_count 1; // Counting up breaks the code
         otr_entries[otr_entries_count][1]=xx[i].previousElementSibling.innerHTML;
         otr_entries[otr_entries_count][2]=xx[i].innerHTML;
         window.alert(otr_entries[otr_entries_count][1]); // No output, script totally stops
         window.alert(otr_entries[otr_entries_count][2]); // No output, script totally stops
      }
   }

EDIT:

This is my solution, thanks to peters help. Works perfectly fine.

   var otr_entries=[];
   var otr_entries_count=-1;

   some_working_for_loop()
   {
      if(is_important_value_to_save())
      {
         otr_entries_count=otr_entries_count 1;
         otr_entries.push(otr_entries_count,xx[i].previousElementSibling.innerHTML,xx[i].innerHTML)
         window.alert(otr_entries[otr_entries_count][1]); // Expected output
         window.alert(otr_entries[otr_entries_count][2]); // Expected output
      }
   }

CodePudding user response：

If in the loop you’re trying to add to the array you need to do otr_entries.push([count,"something","something2"]).

Also, if you’re adding to the array you shouldn’t be using that same array as your loop control.

CodePudding user response：

You're just incrementing the counter before you add new item in the array. The solution is to move the counter incrementing line at the end:

This worked for me

const otr_entries=[[0,"",""]];
const otr_entries_count=0;

for(const entry of otr_entries) {
    // condition
    if(true) {
        otr_entries[otr_entries_count][1]='something';
        otr_entries[otr_entries_count][2]='something else'
        window.alert(otr_entries[otr_entries_count][1]);
        window.alert(otr_entries[otr_entries_count][2]);
        otr_entries_count =1;
    }
}