How to compress an image in a proportional manner after the specified size is exceeded by asp.net

Copy codeThe Code is as follows:
/// <Summary>
/// Compress the image
/// </Summary>
/// <Returns> </returns>
Public string ResizePic ()
{
# Region Compression Image start
Bool IsImgFile = true; // determines whether it is an image file.
String filePathName = "123"; // file storage path (Folder name)
String fileName = "a.jpg"; // Original Name of the uploaded file
String fileSysName = DateTime. Now. ToString ("yyyyMMddHHmmssfff") + "_" + fileName; // modified file name
String filePath = ""; // file path
String strImgPath = "/fileupload/"; // upload path
If (IsImgFile)
{
Int maxWidth = 600; // maximum Image Width
Int maxHeight = 400; // maximum Image Height
System. Drawing. Image imgPhoto =
System. Drawing. Image. FromFile (Server. MapPath (strImgPath) + filePathName + "/" + fileSysName );
Int imgWidth = imgPhoto. Width;
Int imgHeight = imgPhoto. Height;
If (imgWidth> imgHeight) // if the width exceeds the height, the compression is based on the width.
{
If (imgWidth> maxWidth) // if the image width exceeds the limit
{
Float toImgWidth = maxWidth; // The width of the compressed image.
Float toImgHeight = imgHeight/(float) (imgWidth/toImgWidth); // The height of the image after compression

System. Drawing. Bitmap img = new System. Drawing. Bitmap (imgPhoto,
Int. Parse (toImgWidth. ToString ()),
Int. Parse (toImgHeight. ToString ()));
String strResizePicName = Server. MapPath (strImgPath) + filePathName + "/_ small _" + fileSysName;
Img. Save (strResizePicName); // Save the compressed image
FilePath = strImgPath + filePathName + "/_ small _" + fileSysName; // return the compressed image path.
}
}
Else
{
If (imgHeight> maxHeight)
{
Float toImgHeight1 = maxHeight;
Float toImgWidth1 = imgWidth/(float) (imgHeight/toImgHeight1 );

System. Drawing. Bitmap img = new System. Drawing. Bitmap (imgPhoto,
Int. Parse (toImgWidth1.ToString ()),
Int. Parse (toImgHeight1.ToString ()));
String strResizePicName = Server. MapPath (strImgPath) + filePathName + "/_ small _" + fileSysName;
Img. Save (strResizePicName );
FilePath = strImgPath + filePathName + "/_ small _" + fileSysName;
}
}
}
Return filePath;
# Endregion
}