如何使用Epplus在Excel中从Base64编码图像中插入图片

Question

I have an image in a format Base64. I need to show in a picture cell from Base64 encoded image.

Answer 1

This is how I have fixed this one in my code.

var receiptSheet = package.Workbook.Worksheets.Add("Receipt");
int rowIndex = 1;
int columnIndex = 1;

var base64String =  fromDataBase;
base64String = base64String.Replace(" ", "+");
int mod4 = base64String.Length % 4;
if (mod4 > 0)
{
    base64String += new string('=', 4 - mod4);
}

var image = Base64StringToBitmap(base64String);
ExcelPicture picture = null;
if (image != null)
{
    picture = receiptSheet.Drawings.AddPicture("pic" + rowIndex.ToString() + columnIndex.ToString(), image);
    picture.From.Column = columnIndex;
    picture.From.Row = rowIndex;
    picture.SetSize(600, 400);
}
package.Save();

private Bitmap Base64StringToBitmap(string base64String)
{
    var bitmapData = Convert.FromBase64String(FixBase64ForImage(base64String));
    var streamBitmap = new System.IO.MemoryStream(bitmapData);
    var bitmap = new Bitmap((Bitmap)Image.FromStream(streamBitmap));
    return bitmap;
}

private string FixBase64ForImage(string Image)
{
   var sbText = new System.Text.StringBuilder(Image, Image.Length);
   sbText.Replace("\r\n", String.Empty); 
   sbText.Replace(" ", String.Empty);
   return sbText.ToString();
}