How to Retrieve String Data from a SqlDataReader in ASP.NET/C#?

Extracting String Data from an ASP.NET/C# SqlDataReader

This guide demonstrates how to retrieve string data from a SQL Server database using a SqlDataReader in ASP.NET/C#. SqlDataReader offers a forward-only, read-only access method for efficiently processing query results.

Retrieving string values is a frequent task. The GetString() method provides a straightforward approach:

<code class="language-csharp">using (SqlDataReader reader = command.ExecuteReader())
{
    while (reader.Read())
    {
        string retrievedString = reader.GetString(0); // Accesses the first column (index 0)
        // Further processing of the string, e.g., adding to a list:
        myStringList.Add(retrievedString); 
    }
}</code>

This example assumes command is a properly initialized SqlCommand object. The using statement ensures the SqlDataReader is correctly closed and resources are released.

The while (reader.Read()) loop iterates through each row of the result set. reader.Read() returns true if a row is available, and false otherwise.

Inside the loop, reader.GetString(columnIndex) retrieves the string value from the specified column. The columnIndex parameter is zero-based (the first column is 0). The retrieved string is then stored in retrievedString for subsequent use, such as adding it to a list (myStringList). Remember to declare myStringList (e.g., List<string> myStringList = new List<string>();) before the using block.

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