如何访问for循环的索引

Question

const table = document.createElement("table");
table.className = "table";
let indexArray = [1, 2, 3, 4, 5];
    for (let i = 0; i <= indexArray.length; i++) {
      if (indexArray.length === i[1]) {
        const th = document.createElement("th");
        th.innerText = "Global";
        th.style.padding = "20px";
        table.appendChild(th);
      }
}

嘿，我试图访问for循环的索引，为第一个索引提供全局文本名称，但我在这里得到全局文本5次，而不是一次。任何建议

Answer 1

几件事

一个的HTML无效

也许你是这个意思？我猜是因为你没有发布预期的输出

​

const table = document.createElement("table");
table.className = "table";
let indexArray = [1, 2, 3, 4, 5];
for (let i = 0; i < indexArray.length; i++) {
  if (i === 0) {
    var tr = document.createElement("tr");
  }
  var th = document.createElement("th");
  th.innerText = "Global "+i;
  th.style.padding = "20px";
  tr.appendChild(th);

}
table.appendChild(tr)
document.body.appendChild(table)

​

或者这个

​

const table = document.createElement("table");
table.className = "table";
let indexArray = [1, 2, 3, 4, 5];
for (let i = 0; i < indexArray.length; i++) {
  var tr = document.createElement("tr");
  if (i === 0) {
    var th = document.createElement("th");
    th.innerText = "Global";
    th.style.padding = "20px";
    tr.appendChild(th);

  } else {
    var td = document.createElement("td")
    td.textContent = indexArray[i]
    tr.appendChild(td)
  }
  table.appendChild(tr)
}

document.body.appendChild(table)

​

或者这个

​

const table = document.createElement("table");
table.className = "table";
let indexArray = [1, 2, 3, 4, 5];
const text = ["Global", "Local", "Special", "General", "Something else"]
var tr = document.createElement("tr");

for (let i = 0; i < indexArray.length; i++) {
  const th = document.createElement("th");
  th.innerText = text[i];
  th.style.padding = "20px";
  tr.appendChild(th);
}
table.appendChild(tr)

document.body.appendChild(table)

​