Layui layer.open 无法获取content里面的input的值

<div id="search_ebook_vcode" style="display: none;">
    <div class="layui-form" style="margin: 10px;">
        <div class="layui-form-item">
            <label class="layui-form-label">验证码</label>
            <div class="layui-input-block">
                <input type="text" name="search_vcode" id="search_vcode" placeholder="请输入验证码" autocomplete="off" class="layui-input">
            </div>
        </div>
        <div class="layui-form-item">
            <div class="layui-input-block">
                <img id="captchaPic" src="{$cfg[weburl]}index.php?comment-vcode-name-searchvcode" onclick="this.src='{$cfg[weburl]}index.php?comment-vcode-name-searchvcode-r-'+Math.random();" alt="验证码">
            </div>
        </div>
    </div>
</div>

<script>
    layui.use(['form','layer'], function () {
        var layer = layui.layer, $ = layui.$, form = layui.form;
        $(".search_ebook").click(function () {
            var keyword = $('input[name="keyword"]').val();
            if(keyword == ''){
                layer.msg("请输入搜索关键字", {icon: 5});
            }else{
                layer.open({
                    id: 'search_open',
                    type: 1,
                    title: '请输入验证码',
                    shade: 0.6,
                    shadeClose: true,
                    maxmin: true,
                    anim: 0,
                    content: $("#search_ebook_vcode").html(),
                    btn: ['确定', '取消'],
                    btn1: function(index, layero){
                        var search_vcode = $("#search_vcode").val();
                        alert(search_vcode);
                    }
                });
            }
        });
    });
</script>

点击【确定】就是不能获取input的值，总是为空字符串。

后来在网上查找资料，原来这是个比较普遍的bug，原来是layer.open的content参数，应该写成

content: $("#search_ebook_vcode"),

不要后面的html(),去掉后调试正常获取了input的值。

特此记录~~~

layer.open({
	id: 'search_open',
	type: 1,
	title: '请输入验证码',
	shade: 0.6,
	shadeClose: true,
	maxmin: true,
	anim: 0,
	content: $("#search_ebook_vcode"),
	btn: ['确定', '取消'],
	btn1: function(index, layero){
		var search_vcode = $("#search_vcode").val();
		alert(search_vcode);
	}
});