我尝试通过这段代码输出数组
alphabet
作为一系列列表项插入到实际标记中的现有无序列表中。我已经将数组转换为列表项,但我不知道如何告诉它将自己附加到现有的无序列表<ul id="itemList"></ul>
中。var itemsExist = true;
var indexNum = 0;
var unorderedList = document.getElementById('itemList');
var alphabet= new Array("A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z");
function write_letters(){
for (i = 0; i < alphabet.length; i++ ) {
document.write('<li>' + alphabet[indexNum++] + '</li>');
}
}
if (itemsExist){
write_letters();
} else {
document.write("error!");
}