.NET二進(jìn)制圖片存儲與讀取的常見方法
.NET二進(jìn)制圖片存儲與讀取的常見方法有以下幾種:
.NET二進(jìn)制圖片存儲:以二進(jìn)制的形式存儲圖片時,要把數(shù)據(jù)庫中的字段設(shè)置為Image數(shù)據(jù)類型(SQL Server),存儲的數(shù)據(jù)是Byte[].
1.參數(shù)是圖片路徑:返回Byte[]類型:
- public byte[] GetPictureData(string imagepath)
- {
- /**/////根據(jù)圖片文件的路徑使用文件流打開,并保存為byte[]
- FileStream fs = new FileStream(imagepath, FileMode.Open);//可以是其他重載方法
- byte[] byData = new byte[fs.Length];
- fs.Read(byData, 0, byData.Length);
- fs.Close();
- return byData;
- }
2.參數(shù)類型是Image對象,返回Byte[]類型:
- public byte[] PhotoImageInsert(System.Drawing.Image imgPhoto)
- {
- //將Image轉(zhuǎn)換成流數(shù)據(jù),并保存為byte[]
- MemoryStream mstream = new MemoryStream();
- imgPhoto.Save(mstream, System.Drawing.Imaging.ImageFormat.Bmp);
- byte[] byData = new Byte[mstream.Length];
- mstream.Position = 0;
- mstream.Read(byData, 0, byData.Length);
- mstream.Close();
- return byData;
- }
好了,這樣通過上面的方法就可以把圖片轉(zhuǎn)換成Byte[]對象,然后就把這個對象保存到數(shù)據(jù)庫中去就實現(xiàn)了把圖片的二進(jìn)制格式保存到數(shù)據(jù)庫中去了。下面我就談?wù)勅绾伟褦?shù)據(jù)庫中的圖片讀取出來,實際上這是一個相反的過程。
.NET二進(jìn)制圖片讀取:把相應(yīng)的字段轉(zhuǎn)換成Byte[]即:Byte[] bt=(Byte[])XXXX
1.參數(shù)是Byte[]類型,返回值是Image對象:
- public System.Drawing.Image ReturnPhoto(byte[] streamByte)
- {
- System.IO.MemoryStream ms = new System.IO.MemoryStream(streamByte);
- System.Drawing.Image img = System.Drawing.Image.FromStream(ms);
- return img;
- }
2.參數(shù)是Byte[] 類型,沒有返回值,這是針對asp.net中把圖片從輸出到網(wǎng)頁上(Response.BinaryWrite)
- public void WritePhoto(byte[] streamByte)
- {
- // Response.ContentType 的默認(rèn)值為默認(rèn)值為“text/html”
- Response.ContentType = "image/GIF";
- //圖片輸出的類型有: image/GIF image/JPEG
- Response.BinaryWrite(streamByte);
- }
補充:
針對Response.ContentType的值,除了針對圖片的類型外,還有其他的類型:
- Response.ContentType = "application/msword";
- Response.ContentType = "application/x-shockwave-flash";
- Response.ContentType = "application/vnd.ms-excel";
另外可以針對不同的格式,用不同的輸出類型以適合不同的類型:
- switch (dataread("document_type"))
- {
- case "doc":
- Response.ContentType = "application/msword";
- case "swf":
- Response.ContentType = "application/x-shockwave-flash";
- case "xls":
- Response.ContentType = "application/vnd.ms-excel";
- case "gif":
- Response.ContentType = "image/gif";
- case "Jpg":
- Response.ContentType = "image/jpeg";
- }
以上就介紹了.NET二進(jìn)制圖片存儲和讀取的常見方法。
【編輯推薦】