编程礼记

1、图片下载

               

                //设置内容为流格式
               
               

                response.setContentType("application/octet-stream");
               
               

                //添加文件长度
               
               

                response.addHeader("Content-Length", "" + file.length());
               
               

                response.setHeader("Content-Disposition","attachment;filename=file.jpg");
               
               

                当设置ContentType为“response.setContentType("image/jpeg");”时，电脑端可以识别，手机端并不能全部正常识别。
               

2、删除对象发生错误

error:deleted object would be re-saved by cascade (remove deleted object from asso错误

http://blog.163.com/weizonghua_2006/blog/static/13106065620108113618639/

ps：先删除many，再删除one

3、日志记录 最低级别是 debug

DEBUG < INFO < WARN < ERROR

4、c:forEach循环

<c:forEach var="ticketDiscount" items="${ticket_discount}" begin="i" end="i">

${ticketDiscount.name}

</c:forEach>

5、js判断checked

                

                 if
                 (
                 isauto_sell
                 .
                 prop
                 (
                 'checked'
                 )){
                
                

                 //勾选
                
                

                 }else{
                
                

                 //没勾选
                
                

                 }
                

6、jquery绑定事件

                

                 <div
                  
                 class
                 =
                 "2"
                 ></div>
                
                

                 </div>
                  
                
                

                 delegate、 on
                
                

                 $(".3").on('click','.2;',function(){
                
                

                 	
                 alert(1);
                
                

                 })
                

7、js获取iframe中的内容

                

                 <iframe
                  
                 class
                 =
                 "ke-edit-iframe"
                 >
                
                

                 <div
                  
                 class
                 =
                 "ke-content"
                 >
                 fdafasd
                 </div>
                
                

                 </iframe>
                
                


                
                

                 var cont = $(".ke-edit-iframe").contents().find(".ke-content").html();
                

8、创建序列 postgresql

create sequence send_sms_attendance_sequence increment by 1 minvalue 1 no maxvalue start with 1; 

9、js刷新当前页面

                

                 var
                  win 
                 =
                  art
                 .
                 dialog
                 .
                 open
                 .
                 origin
                 ;
                 //来源页面
                
                

                 win.location.reload();
                

10.art.diaog.open使用

art.dialog.open("/eventSet/toTheaterAreaSet?eid="+$('#eid').val(), 
{title:"关联剧场区域",drag: false,fixed: true,lock: true,opacity: 0.3,
	close: function() {
		if(setTheaterAreaNum == 0) {
			var win = art.dialog.open.origin;//来源页面
			 win.location.reload();
			setTheaterAreaNum = 1;
		} else {
			setTheaterAreaNum = 0;
		}
}});

11、值传递与引用传递

1.对象就是传引用
2.原始类型就是传值  byte short int long    float double  boolean  char
3.String类型因为没有提供自身修改的函数，每次操作都是新生成一个String对象，所以要特殊对待。可以认为是传值。

12、社交网络分享插件

http://share.baidu.com/

               

                

                 <div
                  
                 class
                 =
                 "bdsharebuttonbox"
                  
                 style
                 =
                 "
                 display
                 :
                 none
                 ;
                 "
                 >
                
                

                    
                 <a
                  
                 href
                 =
                 "#"
                  
                 class
                 =
                 "bds_more"
                  
                 data-cmd
                 =
                 "more"
                  
                 style
                 =
                 "
                 display
                 :
                 none
                 "
                 ></a>
                
                

                    
                 <a
                  
                 href
                 =
                 "#"
                  
                 class
                 =
                 "bds_tsina"
                  
                 id
                 =
                 "shareToSina"
                  
                 data-cmd
                 =
                 "tsina"
                  
                 title
                 =
                 "分享到新浪微博"
                 ></a>
                
                

                    
                 <a
                  
                 href
                 =
                 "#"
                  
                 class
                 =
                 "bds_tqq"
                   
                 id
                 =
                 "shareToQq"
                  
                 data-cmd
                 =
                 "tqq"
                  
                 title
                 =
                 "分享到腾讯微博"
                 ></a>
                
                

                    
                 <a
                  
                 href
                 =
                 "#"
                  
                 class
                 =
                 "bds_renren"
                  
                 id
                 =
                 "shareToRenren"
                  
                 data-cmd
                 =
                 "renren"
                  
                 title
                 =
                 "分享到人人网"
                 ></a>
                
                

                    
                 <a
                  
                 href
                 =
                 "#"
                  
                 class
                 =
                 "bds_kaixin001"
                  
                 id
                 =
                 "shareToKx"
                  
                 data-cmd
                 =
                 "kaixin001"
                  
                 title
                 =
                 "分享到开心网"
                 ></a>
                
                

                   
                 </div>
                  
                
               
               

                <script>
               
               

                window
                .
                _bd_share_config
                ={
                "common"
                :{
                "bdSnsKey"
                :{},
                "bdText"
                :
                "家有购物"
                ,
                "bdUrl"
                :
                "www.jyh.com"
                ,
                 
                "bdMini"
                :
                "2"
                ,
                "bdMiniList"
                :
                false
                ,
                "bdPic"
                :
                ""
                ,
                "bdStyle"
                :
                "1"
                ,
                "bdSize"
                :
                "16"
                },
                "share"
                :{
                "bdText"
                :
                ""
                ,
                "bdUrl"
                :
                ""
                }};
                with
                (
                document
                )
                0
                [(
                getElementsByTagName
                (
                'head'
                )[
                0
                ]||
                body
                ).
                appendChild
                (
                createElement
                (
                'script'
                )).
                src
                =
                'http://bdimg.share.baidu.com/static/api/js/share.js?v=89860593.js?cdnversion='
                +~(-
                new
                 
                Date
                ()/
                36e5
                )];
               
               

                </script>
               

修改

window._bd_share_config.share.bdText = content;

window._bd_share_config.share.bdUrl = url;

达到修改分享内容与链接的效果。默认分享内容为当前title，分享链接为当前链接。

建议：将自带div隐藏，单独设计分享图标，再通过模拟点击自带的图标，点击效果需要用纯js实现，jquery点击无效。

13、当页面上存在form时，刷新页面时浏览器可能会弹出提示框。

14、top.postmessage window.message 向上级传送信息

15、js中if(str)，判断str是不是一个对象，是对象之后继续其它判断。

16、setTimeout

setTimeout里的方法需以 function(){}包围，才可顺利执行。