H5 复制粘贴文本
<p>
<span>单号:</span>
<span id="inviteCode">34932040</span>
<span @click='copy'>复制</span>
</p>
copy() {
var orderNum = document.getElementById("inviteCode").innerText;
var oInput = document.createElement("input");
oInput.value = orderNum;
document.body.appendChild(oInput);
oInput.select(); // 选择对象
document.execCommand("Copy"); // 执行浏览器复制命令
oInput.className = "oInput";
oInput.style.display = "none";
alert('复制成功');
}