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POHow to convert an SQL Server BLOB string to System.Drawing.Image?
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copied!<p>How can I convert a BLOB represented as a string to a System.Drawing.Image type?</p> <h3>Background</h3> <p>I am going to import information about users together with their photo from a csv file using c#. The proprietary SDK that I use requires the photo to be a System.Drawing.Image</p> <p>Below is an example of the csv file. </p> <pre><code>surname firstname photo Blogs Joe 0xFFD8FFE000104A46494600010101005F005F0000FFDB0043000D090A </code></pre> <p>The photo field is actually 5k chars long and is a direct export of the BLOB field value in the sql server db. We have just taken the raw value from the database field and exported it to the csv file.</p> <p>Below is the code that demonstrates how far I have got. The <code>cvsuser</code> variable represents one row of the csv file.</p> <pre><code>// We need to convert the photo from a string to a byte array string strPhoto = null; strPhoto = csvuser.photo; // The string that represents the BLOB byte[] bytes = new byte[strPhoto.Length * sizeof(char)]; System.Buffer.BlockCopy(strPhoto.ToCharArray(), 0, bytes, 0, bytes.Length); // Then we create a memory stream that holds the image MemoryStream photostream = new MemoryStream( bytes ); // Then we can create a System.Drawing.Image by using the Memory stream var photo = Image.FromStream(photostream); </code></pre> <p>However, the <code>Image.FromStream()</code> line throws a System.ArgumentException with the message "Parameter is not valid."</p> <h3>Question</h3> <p>How can I convert the BLOB represented as a string to a System.Drawing.Image type? </p> <p>The examples I have seen previously would, for example, fetch the blob straight from the database or reading the image from a file.</p>

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