function selectSeal() {

document.getElementById("sealinfo").click();

}


function updateSeal(sealimageupdateId) {

var sealinfo = {};

sealinfo.sealimageupdateId = sealimageupdateId;

$.ajaxFileUpload( {

url : '${pageContext.request.contextPath}/seal/uploadSealInfo.do',

secureuri : false,

fileElementId : 'sealinfo',

dataType : 'json',

data : sealinfo,

success : function(data, status) {

if (data == "0") {

location.reload();

} else {

alert("上传失败");

}

},

error : function(data, status, e) {

alert(e);

}

});

}


<input id="btn_sealchange" type="button" value="更改印章"
																				class="btn btn-info"
																				onclick="selectSeal(${seal.sealImageId});">
																			<input id="sealinfo" name="file" type="file"
																				onchange="updateSeal(${seal.sealImageId});"
																				style="display: none">


	@RequestMapping(value = "uploadSealInfo")
	public @ResponseBody String uploadSealInfo(
			@RequestParam(value = "file", required = false) MultipartFile file,
			@RequestParam(value = "sealimageupdateId") Long id,HttpServletResponse response) {
		try {
			byte[] sealByte = file.getBytes();
			SealInfo sealInfo = new SealInfo();
			sealInfo.setFileData(sealByte);
			sealInfo.setId(id);
			this.sealService.uploadSeal(sealInfo);
			return "0";
		} catch (IOException e) {
			e.printStackTrace();
			return "-1";
		}

	}
	
	
	
	
//////更新mysql blob  

	<update id="updateByPrimaryKeySelective" parameterType="com.itrus.msign.entity.SealInfo">
		update seal_info set file_data=#{fileData}
		where id = #{id,jdbcType=BIGINT}
   </update>