Document and Video file format extension verification and image real verification help class, file format truth

Document and Video file format extension verification and image real verification help class, file format truth

Using System; using System. collections. generic; using System. linq; using System. text; using System. IO; namespace Reform. folderManage. cls {public class FileHelper {/// <summary> /// image class header encoding /// </summary> public enum ImgExtension {JPG = 255216, GIF = 7173, BMP = 1, 6677, PNG = 13780} /// <summary> // file type determination // </summary> /// <param name = "fileName"> file </param> /// <param name = "fileType"> file type </param> /// <returns> </returns> public static bool IsRealFile (string fileName, string fileType) {string fileExt = Path. getExtension (fileName ). toLower (); // get the file suffix if (fileType = "image") {if (IsAllowedExtension (fileName) return true;} if (fileType = "video ") {List <string> list = new List <string> (); list. add (". flv "); list. add (". wmv "); list. add (". avi "); list. add (". 3gp "); Path. getExtension (fileName ). toLower (); // get the file suffix return IsExistEx (list, fileExt);} if (fileType = "document ") {List <string> list = new List <string> (); list. add (". doc "); list. add (". pdf "); return IsExistEx (list, fileExt);} return false ;} /// <summary> /// determine the file suffix /// </summary> private static bool IsExistEx (List <string> list, string fileExt) {if (list. contains (fileExt) // {return true;} return false;} in the list ;} # region image processing // <summary> /// whether the image type is true // </summary> public static bool IsAllowedExtension (string imgFileName) {System. IO. fileStream fs = new System. IO. fileStream (imgFileName, System. IO. fileMode. open, System. IO. fileAccess. read); System. IO. binaryReader br = new System. IO. binaryReader (fs); string fileclass = ""; byte buffer; try {buffer = br. readByte (); fileclass = buffer. toString (); buffer = br. readByte (); fileclass + = buffer. toString ();} catch {} br. close (); fs. close (); ImgExtension [] fileEx = {ImgExtension. BMP, ImgExtension. GIF, ImgExtension. JPG, ImgExtension. PNG}; foreach (ImgExtension fe in fileEx) {if (Int32.Parse (fileclass) = (int) fe) return true ;}return false ;}# endregion }}