C#程序设计技巧小结

获取文件的版本信息:FileVersionInfo myFileVersionInfo1 = FileVersionInfo.GetVersionInfo( "D:\\TEST.DLL" );textBox1.Text="版本号: " + myFileVersionInfo1.FileVersion;      更改文件属性,删除只读文件：    下例欲将E:\test.txt文件拷贝至D:\tmp\test.txt,但D:\tmp\test.txt已经存在.//File.Copy( sourceFile,destinationFile,true ); 用来拷贝文件//当destinationFile已经存在时,无法将文件file1拷贝到目标文件,//因此先删除destination文件,File.Delete( )方法不能删除只读文件,//因此,如果文件属性为只读( Attributes属性中会包含有"ReadOnly" ),//先把文件属性重置为Normal,然后再删除:string file1="E:\\test.txt";string destinationFile="d:\\tmp\\test.txt";if( File.Exists( destinationFile ) ){    FileInfo fi=new FileInfo( destinationFile );    if( fi.Attributes.ToString( ).IndexOf( "ReadOnly" )!=-1 )    fi.Attributes=FileAttributes.Normal;    File.Delete( destinationFile );}File.Copy( file1,destinationFile,true ); C#中字符串的格式化及转换成数值的方法     字符串转换成数字,比如"1234"转换成数字1234:string str="1234";int i=Convert.ToInt32( str );      格式化字符串,向长度小于30的字符串末尾添加特定字符,补足n个字符,使用String类的PadRight( int,char )方法：String str="1234";str=str.PadRight( 30,' ' ) //向长度小于30的字符串末尾添加空格,补足30个字符     按行读写文件    判断文件是否存在:File.Exists( string filePath )    判断目录是否存在:Directory.Exists( "D:\\LastestVersion" )     按行读取文件：int fileCount=0;// Open the file just specified such that no one else can use it.StreamReader sr = new StreamReader( textBox1.Text.Trim( ) );while( sr.Peek( ) > -1 )//StreamReader.Peek( )返回下一个可用字符,但不使用它{    listBox1.Items.Add( sr.ReadLine( ) );    fileCount++;}sr.Close( );     按行写入文件：StreamWriter sw = new StreamWriter( "D:\\result.txt" );for( int i=0;i<10;i++ ){    sw.WriteLine( "这是第"+i.ToString( )+"行数据" );}     文件目录对话框的使用    文件对话框即过滤条件的使用：string resultFile="";OpenFileDialog openFileDialog1 = new OpenFileDialog( );openFileDialog1.InitialDirectory = "D:\\Patch" ;openFileDialog1.Filter = "All files ( *.* )|*.*|txt files ( *.txt )|*.txt" ;openFileDialog1.FilterIndex = 2 ;openFileDialog1.RestoreDirectory = true ;if( openFileDialog1.ShowDialog( ) == DialogResult.OK )resultFile=openFileDialog1.FileName;      目录对话框的使用：string resultFolder="";FolderBrowserDialog openFolderDialog1=new FolderBrowserDialog( );openFolderDialog1.RootFolder=Environment.SpecialFolder.MyComputer; if( openFolderDialog1.ShowDialog( )==DialogResult.OK )resultFolder=openFolderDialog1.SelectedPath;