Unable to cast object of type 'System.String' to type 'System.Byte[]'. Exception

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I cant fix this exception, can someone help me with this.
Heres the code:

DataTable dt = new DataTable();

    dt.Columns.Add("Marker", typeof(string));
    dt.Columns.Add("Desc", typeof(string));
    dt.Columns.Add("Page", typeof(string));


    dt.Rows.Add("A1", "Desc1", "1");
    dt.Rows.Add("A2", "Desc2", "2");
    dt.Rows.Add("A3", "Desc3", "3");
    dt.Rows.Add("A4", "Desc4", "4");

    byte[] data = (byte[])dt.Rows[0][0];

    richTextBox1.Rtf = System.Text.Encoding.Unicode.GetString(data);

Thanks in advance;

Posted 8-Nov-10 20:27pm

holyoxx

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2 solutions

Solution 1

try this

byte[] data = System.Text.Encoding.Unicode.GetBytes(dt.Rows[0][0].ToString ());

instead of

byte[] data = (byte[])dt.Rows[0][0];

Posted 8-Nov-10 20:35pm

Rajesh Anuhya

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Rajesh Anuhya 9-Nov-10 2:36am

Consider below answer also by David Ewen

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David Ewen · Accepted Answer · 2010-11-08T20:35:00

Solution 2

The last 2 lines

MIDL

byte[] data = (byte[])dt.Rows[0][0];
richTextBox1.Rtf = System.Text.Encoding.Unicode.GetString(data);

Should be

richTextBox1.Rtf = dt.Rows[0][0].ToString();

There is no need to try to convert the string to a byte array and back to a string.

Posted 8-Nov-10 20:35pm

David Ewen