变量和字符串的串联错误

Question

I would like to pass an argument to another page but it turns out that it's undefined.

getAccount() returns a list of json. Firstly, I display those json objects one by one on HTML and when the user clicks each, the accDetail[i].accNo is set as local storage and will be passed to next page.

var accDetail=getAccounts();


for(var i =0;i<accDetail.length;i++) {
  document.getElementById("demo").innerHTML+='<a href="accountdetails.html" onclick="getAcc('+accDetail[i].accNo+')">'+accDetail[i].accNo +'</a>'+' '+ accDetail[i].accType+' '+ accDetail[i].balance+'<br>';

}

This is the function to set the item as local storage.

function getAcc(item)
{
    localStorage.setItem("accNo",item); }

It does not display the value I want, is the way I concatenate it wrong?

Answer 1

Your onclick handler is going to be literally getAcc(accDetail[i].accNo) (try viewing in Inspect Element), which won't work because accDetail is not defined in the event handler. You need to change your Javascript so that it writes getAcc(0) , getAcc(1) , etc where 0, 1 are the different accNo .

Here is a small example I wrote, hopefully you can extend it to solve your problem:

var accNo = [1, 2, 3, 4];
  for(var i = 0;i < accNo.length; i++) {
    var line = '<a href="accountdetails.html" onclick="getAcc(' + accNo[i] + ')">' + accNo[i] + '</a> <br>';
    console.log(line);
    document.getElementById("demo").innerHTML += line;
  }

Answer 2

First Make sure your function getting correct value

Try Using window object instead

function getAcc(item)
{
    localStorage.setItem("accNo",item); 
}

Replace with 

function getAcc(item)
{
console.log(item); // Please check you get item correct not undefined
window.accNo = item;
}

And whereever you want just use window.accNo