1.使用DOS命令写的路径有空格时(例:C:\Program Files\QQ\),会将有空格的文件夹识别错误(例:C:\Program\QQ\)
解决方案:在路径用双引号引起来(例:"C:\Program Files\QQ\")
2.如果写一个死循环,执行期间,对当前线程执行的cpu核心占用100%, 如果对一个死循环开2个线程,则CPU(2核)占用为100%,4核CPU为50%,依次类推.
3.C#给C++传递委托时,此委托必须必须定义为静态,否则会出现空指针异常,此异常不会有任何提示,会在.net bin目录下的Debug/Release Crash文件,双击
用visual studio打开启动,提示“0xC0000005: 读取位置 0x0000000000000000 时发生访问冲突”,此为空指针异常。
示例代码:
public delegate int LPFNEVENTCALLBACK(ushort wEvent, int nReference, uint dwParam, uint dwUser); Class calss1 { static LPFNEVENTCALLBACK Ccallback = MyMethod; //此变量必须为静态!! void MyMethod(ushort wEvent, int nReference, uint dwParam, uint dwUser) { } }
4.获取注册表值
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
object appPath = Microsoft.Win32.Registry.LocalMachine.OpenSubKey("SOFTWARE").OpenSubKey("Wow6432Node").OpenSubKey("ShCti").GetValue("AppPath");
5.标记类或方法过时:加上属性 [Obsolete]
6.在线QQ代码,无需加还有,立即发起临时会话
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
<a target="blank" href="tencent://message/?Menu=yes&uin=[QQ号码]&Site=qq&Service=300&sigT=45a1e5847943b64c6ff3990f8a9e644d2b31356cb0b4ac6b24663a3c8dd0f8aa12a545b1714f9d45"> <img border="0" SRC="http://wpa.qq.com/pa?p=2:[QQ号码]:51" alt="点击这里给我发消息"> </a>
7.统一预处理Button(或其他服务器控件),并可控制是否继续执行Button事件
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
protected override void RaisePostBackEvent(IPostBackEventHandler sourceControl, string eventArgument) { if (sourceControl is Button) { if (!RoleBLL.ButtonRight(CurUser.RoleCode, (sourceControl as Button).ID))//这里还要传入页面地址 JsControl.Show(this, "您没有权限"); else base.RaisePostBackEvent(sourceControl, eventArgument); } }
8.通过每页行数和总数据量获取总页数
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
(int)Math.Ceiling((double)RecordCount / (double)PageSize);
9.匹配固定电话正则
^(010|02\\d|0[3-9]\\d{2})?\\d{6,8}$
10.取固定电话区号
^(010|02\\d|0[3-9]\\d{2})\\d{6,8}$