显示手指形状 cursor:pointer
定义上传按扭样式
<form method="post" enctype="multipart/form-data">
<img src="./Chrysanthemum.jpg" id="btn1" onclick="myfile.click();">
<input name="file" type="file" id="myfile" style="display:none">
<input type="submit" value="upload" />
</form>
