C# (CSharp) MySQLDataReader.GetBytes Examples

Programming Language: C# (CSharp)

Class/Type: MySQLDataReader

Method/Function: GetBytes

Examples at hotexamples.com: 1

The MySqlDataReader.GetBytes method gets the data from the specified column as an array of bytes. It takes two parameters - the column index and an array to hold the returned bytes.

Example:

using MySql.Data.MySqlClient;

// Create a MySqlConnection object
MySqlConnection conn = new MySqlConnection("Server=localhost;Database=mydb;Uid=myusername;Pwd=mypassword;");

// Open the connection
conn.Open();

// Create a MySqlCommand object
MySqlCommand cmd = new MySqlCommand("SELECT * FROM mytable", conn);

// Execute the query and get a MySqlDataReader object
MySqlDataReader rdr = cmd.ExecuteReader();

// Read the data
while (rdr.Read())
{
    byte[] bytes = new byte[100]; // create an array to hold the bytes
    rdr.GetBytes(0, 0, bytes, 0, 100); // get the bytes from the first column
    // use the bytes as needed
}

// Close the reader and connection
rdr.Close();
conn.Close();

In this example, we first create a MySqlConnection object, open the connection, and create a MySqlCommand object with a SELECT query. We then execute the query and get a MySqlDataReader object to read the data. Inside the while loop, we create an array to hold the bytes and use the GetBytes method to get the bytes from the first column of the current row. We can then use the bytes as needed. Finally, we close the reader and the connection. The package library used in this example is MySql.Data.

C# (CSharp) MySQLDataReader.GetBytes - 1 examples found. These are the top rated real world C# (CSharp) examples of MySQLDataReader.GetBytes extracted from open source projects. You can rate examples to help us improve the quality of examples.

Frequently Used Methods

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Read(30)

GetString(26)

Close(14)

GetValue(12)

GetName(3)

GetBytes(1)

GetInt32(1)

GetValues(1)

Example #1

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File: Class1.cs Project: ultralight32/MySqlDriverCs

        public string getBLOBFile(string fileName, MySQLDataReader reader, int fieldnumber)
        {
            FileStream   fs;
            BinaryWriter bw;
            int          bufferSize = 4096;

            byte[] outbyte = new byte[bufferSize];
            long   retval;
            long   startIndex = 0;

            try
            {
                // Reset the starting byte for the new BLOB.
                startIndex = 0;

                retval = reader.GetBytes(fieldnumber, startIndex, outbyte, 0, bufferSize);

                if (retval == 0)
                {
                    return("");
                }

                fs = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.Write);
                bw = new BinaryWriter(fs);

                // Continue reading and writing while there are bytes beyond the size of the buffer.
                while (retval == bufferSize)
                {
                    bw.Write(outbyte);
                    bw.Flush();

                    // Reposition the start index to the end of the last buffer and fill the buffer.
                    startIndex += bufferSize;
                    retval      = reader.GetBytes(fieldnumber, startIndex, outbyte, 0, bufferSize);
                }

                // Write the remaining buffer.
                bw.Write(outbyte, 0, (int)retval);
                bw.Flush();

                // Close the output file.
                bw.Close();
                fs.Close();

                fileName = new FileInfo(fileName).FullName;
            }
            catch (IOException e)
            {
                throw e;
            }

            return(fileName);
        }