如何在不知道其值的情况下获取 javascript 中的数组索引

Question

i am creating an array of textboxes. and each box has a corresponding del and edit option.

 for(i=0;i<5;i++)
    {
    <input type='text' id='pp_insti' name='pp_insti[]' value='"+institute+"' style='display:none;'>
    <input type='button' class='edit-button' id='pp_edit name='pp_edit[]' onclick='pp_edit();'/>
<input type='button' class='del-button' id='pp_del name='pp_del[]' onclick='pp_del();'/>
    }

what value of index should i pass for pp_edit so i know which pp_inst[] to edit.

can anyone help.. thanks

Answer 1

You're trying to create several textboxes with the same ID ( pp_insti ). This is not allowed.

Instead, you could give them IDs such as pp_insti_1 , pp_insti_2 etc, based on the value of i . You could then pass the value of i to the edit and delete functions as well, to be able to find the text box of interest.

Answer 2

You don't need to pass a value, because the onclick handler is run with an event variable automatically passed to it. Therefore change your function definition of pp_edit() to pp_edit(ev) , and then inside the function use elem=ev.target , where elem will be the DOM element that was clicked on.

Alternatively, you could pass the this keyword to each call of pp_edit: onclick='pp_edit(this); , then define pp_edit: pp_edit(obj) . Now in pp_edit, obj refers to the clicked element.

The third alternative is to set the onclick handlers programatically, instead of in-line:

for(....){
  elem=document.createElement('...');
  elem.onclick=pp_edit;
}

Now, when pp_edit is called, it will be within the context of the clicked element, and inside pp_edit, the this keyword will refer to the clicked element.

NOTE: as another user pointed out, your code is invalid, but I am assuming you posted it that way to get your point across. If not, you definitely need to lookup functions like document.createElement() .