显示存储的图像

软件技术国家教学资源库建设项目软件开发素材之C源代码一、功能简介显示存储的图像二、创建或搜集相关信息搜集单位重庆电子工程职业学院搜集时间20120805来源互联网三、适用对象学生、教师、C及ASPNET项目开发人员、相关技术人员等。四、功能简介显示数据库存储的图像。五、程序代码程序名称FORM1CSUSINGSYSTEMUSINGSYSTEMCOLLECTIONSGENERICUSINGSYSTEMCOMPONENTMODELUSINGSYSTEMDATAUSINGSYSTEMDRAWINGUSINGSYSTEMLINQUSINGSYSTEMTEXTUSINGSYSTEMWINDOWSFORMSNAMESPACEDISPLAYIMAGESAPPPUBLICPARTIALCLASSFORM1FORMPUBLICFORM1INITIALIZECOMPONENTPRIVATEVOIDFORM1_LOADOBJECTSENDER,EVENTARGSEDATAIMAGEHELPERDATAIMAGEHELPERNEWDATAIMAGEHELPERDATATABLEDTDATAIMAGEHELPERGETSQLTABLE“SELECTID,IMAGENAMEFROMTB_IMAGE“,“DT_IMAGE“IFDTROWSCOUNT0COMBOBOX1DATASOURCEDTCOMBOBOX1DISPLAYMEMBER“IMAGENAME“COMBOBOX1VALUEMEMBER“ID“COMBOBOX1_SELECTEDINDEXCHANGEDSENDER,EPRIVATEVOIDCOMBOBOX1_SELECTEDINDEXCHANGEDOBJECTSENDER,EVENTARGSETRYDATAIMAGEHELPERDATAIMAGEHELPERNEWDATAIMAGEHELPERBYTEIMAGEBYTEBYTEDATAIMAGEHELPEROLEEXECUTEREADER“SELECTIMAGEBYTEFROMTB_IMAGEWHEREID“COMBOBOX1SELECTEDVALUEPB_IMAGEOUTIMAGEDATAIMAGEHELPERGETIMAGEBYBEYTIMAGEBYTECATCHEXCEPTION/THROW程序名称DISPLAYIMAGESAPPCSUSINGSYSTEMUSINGSYSTEMCOLLECTIONSGENERICUSINGSYSTEMTEXTUSINGSYSTEMDRAWINGUSINGSYSTEMIONAMESPACEDISPLAYIMAGESAPPCLASSDATAIMAGEHELPERACCESSHELPER/将数据库中读取到的BYTE转换为IMAGE类型/ACCESS数据库内读取到的BYTE/IMAGE类型PUBLICIMAGEGETIMAGEBYBEYTBYTEIMAGEBYTESTREAMSTREAMNEWMEMORYSTREAMIMAGEBYTERETURNIMAGEFROMSTREAMSTREAM/将图片文件转换为BYTE类型/图片文件路径/图片的BYTE流PUBLICBYTEGETBEYTIMAGEBYPATHSTRINGIMAGEPATHFILESTREAMFILESTREAMNEWFILESTREAMIMAGEPATH,FILEMODEOPEN,FILEACCESSREADBINARYREADERBINARYREADERNEWBINARYREADERFILESTREAMBYTEMYBYTENEWBYTEFILESTREAMLENGTHBINARYREADERREADMYBYTE,0,CONVERTTOINT32FILESTREAMLENGTHFILESTREAMCLOSERETURNMYBYTE程序名称ACCESSHELPERCSUSINGSYSTEMUSINGSYSTEMCOLLECTIONSGENERICUSINGSYSTEMTEXTUSINGSYSTEMDATAUSINGSYSTEMDATAOLEDBUSINGSYSTEMDATASQLCLIENTUSINGSYSTEMWINDOWSFORMSNAMESPACEDISPLAYIMAGESAPPPUBLICCLASSACCESSHELPER/ACCESSHELPER/PUBLICSTRINGOLEDBCONNECTIONSTRINGSETOLEDBCONNECTIONSTRINGVALUEGETRETURNOLEDBCONNECTIONSTRING/从配置文件获取定义的SQL连接字符串/PRIVATESTATICSTRINGSTRCONNECTSYSTEMCONFIGURATIONCONFIGURATIONSETTINGSAPPSETTINGS“CONNSTR“PRIVATESTRINGOLEDBCONNECTIONSTRINGPUBLICACCESSHELPER/设置连接字符串OLEDBCONNECTIONSTRING“PROVIDERMICROSOFTJETOLEDB40JETOLEDBDATABASEPASSWORD123456“OLEDBCONNECTIONSTRING“DATASOURCE“APPLICATIONSTARTUPPATH“IMAGEDATAMDBPERSISTSECURITYINFOTRUE“/OLEDBCONNECTIONSTRING“UIDADMIN“/典型连接字符串是“PROVIDERMICROSOFTJETOLEDB40DATASOURCEDATABASENAMEUSERIDUSERNAMEPASSWORDUSERPASSWORD“PUBLICOLEDBCONNECTIONCREATECONNECTION/返回OLEDB的一个连接RETURNNEWOLEDBCONNECTIONOLEDBCONNECTIONSTRING/在内存中建立一个表/要使用的SQL语句/要进行操作的目标表/PUBLICDATATABLEGETSQLTABLESTRINGSELECTSQL,STRINGTABLENAME/获得一个表,2个参数,一个SQL语句,一个表名DATATABLETABLENEWDATATABLETABLENAMEOLEDBCONNECTIONOLECONNECTIONTHISCREATECONNECTIONTRYOLEDBDATAADAPTEROLEDATAADAPTERNEWOLEDBDATAADAPTERSELECTSQL,OLEDBCONNECTIONSTRINGOLEDATAADAPTERFILLTABLECATCHSYSTEMDATAOLEDBOLEDBEXCEPTIONEXTHROWEXCATCHSYSTEMEXCEPTIONEXTHROWEXFINALLYIFOLECONNECTIONSTATECONNECTIONSTATECLOSEDOLECONNECTIONCLOSERETURNTABLE/执行SQL语句/SQL语句/PUBLICINTEXECUTESQLSTRINGCMDTEXT/执行SQL语句,1个参数,为所执行的语句,返回整数值为判断所影响的行数INTIVALUE1OLEDBCONNECTIONOLECONNECIONTHISCREATECONNECTIONOLECONNECIONOPENOLEDBTRANSACTIONOLETRANSACTIONOLECONNECIONBEGINTRANSACTION/新建一事务TRYOLEDBCOMMANDOLECOMMANDNEWOLEDBCOMMANDOLECOMMANDCONNECTIONOLECONNECION/使用的连接OLECOMMANDCOMMANDTEXTCMDTEXT/SQL语句OLECOMMANDTRANSACTIONOLETRANSACTION/建立一个事务IVALUEOLECOMMANDEXECUTENONQUERYOLETRANSACTIONCOMMIT/提交事务CATCHSYSTEMDATAOLEDBOLEDBEXCEPTIONEXOLETRANSACTIONROLLBACK/事务没有执行结束则回滚THROWEXCATCHSYSTEMEXCEPTIONEX2THROWEX2FINALLYOLECONNECIONCLOSERETURNIVALUE/封装根据COMMAND对象填充DATAREADER的方法/返回DATAREADER类型的值/SQL语句/PUBLICOBJECTOLEEXECUTEREADERSTRINGCMDTEXTOLEDBCONNECTIONOLECONNECIONTHISCREATECONNECTIONOLECONNECIONOPENOLEDBTRANSACTIONOLETRANSACTIONOLECONNECIONBEGINTRANSACTIONTRYOLEDBCOMMANDOLECOMMANDNEWOLEDBCOMMANDOLECOMMANDCONNECTIONOLECONNECIONOLECOMMANDCOMMANDTEXTCMDTEXTOLECOMMANDTRANSACTIONOLETRANSACTIONOLEDBDATAREADERDROLECOMMANDEXECUTEREADER/OLETRANSACTIONCOMMIT/如果有数据用WHILE