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![Samuel Kleos](https://uploads.teamtreehouse.com/production/profile-photos/11699126/micro_Square_Photo_-_Tahir.jpg)
Samuel Kleos
Front End Web Development Techdegree Student 13,118 PointsUncaught TypeError: li.appendChild is not a function
Why doesn't my for..in loop work here?
const taskList = document.querySelector('.list-container ul');
const listItems = taskList.children;
// Adding a remove button to a li item.
function addBtnRemove(li) {
let btnRemove = document.createElement('button');
btnRemove.className = 'remove';
btnRemove.textContent = "Remove";
li.appendChild(btnRemove);
}
// Adding a remove button to existing li items
for (let item in listItems ) {
addBtnRemove(item);
}
1 Answer
![Steven Parker](https://uploads.teamtreehouse.com/production/profile-photos/969492/micro_tool_chess_set_2.jpg)
Steven Parker
230,688 PointsThe loop variable (item in this case) of a "for...in" loop will contain a stringified index for each item, but the addBtnRemove function apparently expects to get an element reference as an argument.
Did you perhaps mean to use "for...of" instead?
Samuel Kleos
Front End Web Development Techdegree Student 13,118 PointsSamuel Kleos
Front End Web Development Techdegree Student 13,118 PointsThat's fantastic, I just implemented it thank you.