Common Methods for storing and reading. NET Binary Images

. NET binary image storage and reading methods are as follows:

. NET binary Image storage: When storing images in binary format, you must set the fields in the database to the Image data type (SQL Server). the stored data is Byte [].

1. the parameter is the image path: returned Byte [] type:

 
 

  
  
Public Byte[] GetPictureData (StringImagepath)
  
  
{
  
  
/**///// Open the file stream based on the path of the image file and save itByte[]
  
  
FileStream fs =NewFileStream (imagepath, FileMode. Open );// It Can Be Another overload method 
  
  
Byte[] ByData =New Byte[Fs. Length];
  
  
Fs. Read (byData, 0, byData. Length );
  
  
Fs. Close ();
  
  
ReturnByData;
  
  
}
  
  

 
 

2. If the parameter type is an Image object, the returned Byte [] type is:

 
 

  
  
Public Byte[] PhotoImageInsert (System. Drawing. Image imgPhoto)
  
  
{
  
  
// Convert the Image into streaming data and save it as byte [] 
  
  
MemoryStream mstream =NewMemoryStream ();
  
  
ImgPhoto. Save (mstream, System. Drawing. Imaging. ImageFormat. Bmp );
  
  
Byte[] ByData =NewByte [mstream. Length];
  
  
Mstream. Position = 0;
  
  
Mstream. Read (byData, 0, byData. Length );
  
  
Mstream. Close ();
  
  
ReturnByData;
  
  
}
 
 

Now, we can convert the image into a Byte [] object through the above method, then, the object is saved to the database, and the binary format of the image is saved to the database. Next I will talk about how to read images from the database. In fact, this is the opposite process.

. NET binary image reading: Convert the corresponding fields into Byte []: Byte [] bt = (Byte []) XXXX

1. the parameter is of the Byte [] type, and the returned value is an Image object:

 
 

  
  
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. the parameter is of the Byte [] type and has no return value. This is for asp.net to output the image to the webpage (Response. BinaryWrite)

 
 

  
  
Public VoidWritePhoto (Byte[] StreamByte)
  
  
{
  
  
// The default value of Response. ContentType is "text/html" 
  
  
Response. ContentType ="Image/GIF";
  
  
// Image output types: image/GIF image/JPEG 
  
  
Response. BinaryWrite (streamByte );
  
  
}
 
 

Supplement:

For the value of Response. ContentType, in addition to the image type, there are other types:

 
 

  
  
Response.ContentType = "application/msword";  
  
  
            Response.ContentType = "application/x-shockwave-flash";  
  
  
            Response.ContentType = "application/vnd.ms-excel"; 
 
 

In addition, different output types can be used for different formats:

 
 

  
  
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";  
  
  
            }  
 
 

The preceding describes common methods for storing and reading. NET binary images.

1. Implementation of ASP. NET and SQL Server database image storage
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