如何访问动态创建的复选框并确定选中状态？

<div id="checkboxContainer"></div>
<button onclick="checkSelected()">确定选中状态</button>

// 动态创建复选框
function createCheckbox() {
  var container = document.getElementById("checkboxContainer");
  
  for (var i = 1; i <= 3; i++) {
    var checkbox = document.createElement("input");
    checkbox.type = "checkbox";
    checkbox.id = "checkbox" + i;
    checkbox.value = "选项" + i;
    
    var label = document.createElement("label");
    label.htmlFor = "checkbox" + i;
    label.appendChild(document.createTextNode("选项" + i));
    
    container.appendChild(checkbox);
    container.appendChild(label);
    container.appendChild(document.createElement("br"));
  }
}

// 确定选中状态
function checkSelected() {
  for (var i = 1; i <= 3; i++) {
    var checkbox = document.getElementById("checkbox" + i);
    
    if (checkbox.checked) {
      console.log("复选框" + i + "被选中");
    } else {
      console.log("复选框" + i + "未被选中");
    }
  }
}

// 调用函数创建复选框
createCheckbox();