converting string to image..??

[grawsha2000]

Hi,

I'm trying to convert this simple string into image:

Dim bytes() as byte()=System.text.Encoding.ascii.GetBytes("123")
Dim memStream as System.IO.MemoryStream
Dim img as image


memStream.Write(bytes,0.bytes.length)
img=image.fromstream(memStream) ' an error occurs here


vb.net returns an error: "invlaid parameter" for passing stream to the
image.

I don't want to read stream from file, as I am interested in reading
from input string (textbox).

MTIA,
Grawsha

 

[Mythran]

Hi,

I'm trying to convert this simple string into image:

Dim bytes() as byte()=System.text.Encoding.ascii.GetBytes("123")
Dim memStream as System.IO.MemoryStream
Dim img as image


memStream.Write(bytes,0.bytes.length)
img=image.fromstream(memStream) ' an error occurs here


vb.net returns an error: "invlaid parameter" for passing stream to the
image.

I don't want to read stream from file, as I am interested in reading
from input string (textbox).

MTIA,
Grawsha

Ok, from what I understand, you want to write a string onto a image?

Dim s As String = "123"
Dim bmp As Bitmap = New Bitmap(1, 1)
Dim canvas As Graphics = Graphics.FromImage(bmp)
Dim size As Size
Try
' Measure the string.
size = canvas.MeasureString(s, New Font("Verdana", 12))
Finally
canvas.Dispose()
bmp.Dispose()
End Try

bmp = New Bitmap(size.Width, size.Height)
canvas = Graphics.FromImage(bmp)

Try
canvas.DrawString(s, New Font("Verdana", 12))
Finally
canvas.Dispose()
End Try

' Now bmp contains the valid string.

HTH (untested code, btw, may have a few errors, but should work with minor
fixes).
Mythran

 

[Guest]

well for one....i dont even know what this is making

Dim bytes() as byte()=System.text.Encoding.ascii.GetBytes("123")

try making it either

Dim bytes as byte()=System.text.Encoding.ascii.GetBytes("123")

or

Dim bytes() as byte=System.text.Encoding.ascii.GetBytes("123")


and see how that works

 

[Mythran]

well for one....i dont even know what this is making

Dim bytes() as byte()=System.text.Encoding.ascii.GetBytes("123")

try making it either

Dim bytes as byte()=System.text.Encoding.ascii.GetBytes("123")

or

Dim bytes() as byte=System.text.Encoding.ascii.GetBytes("123")


and see how that works

His problem is that he is trying to load an image from a memory stream that
only contains the bytes of text. The FromStream method expects a byte-array
containing the bytes of an image, not the bytes of a simple string.

By loading the byte-array into an image (FromStream method) he is getting an
exception. So, to do this correctly, he needs to write the string onto an
image using the Graphics class.

HTH

Mythran