Cannot convert from 'system.data.sqlclient.sqlconnection' to 'string'

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When i am returning the connectionstring in string format i am getting an error saying Cannot Convert from 'System.Data.SqlClient.SqlConnection' to 'String'

Can anyone explain me

What I have tried:

public static int ExecuteNonQuery(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
{
    if (connectionString == null || connectionString.Length == 0) throw new ArgumentNullException("connectionString");

    // Create & open a SqlConnection, and dispose of it after we are done
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();

        // Call the overload that takes a connection in place of the connection string
        return ExecuteNonQuery(connection, commandType, commandText, commandParameters);
    }
}

Posted 3-Mar-18 2:04am

Member 8583441

Updated 3-Mar-18 2:46am

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Member 8583441 3-Mar-18 8:05am

The error is at return ExecuteNonQuery(connection, commandType, commandText, commandParameters); this line at connection

2 solutions

Solution 1

Why do you call the same method recursively? You're inside ExecuteNonQuery method and calling it again.

Did you intend to call the ExecoteNonQuery method of the command

C#

...
connection.Open();
SqlCommand command = new SqlCommand(commandText, connection);
command.Connection.Open();
command.ExecuteNonQuery();
...

Posted 3-Mar-18 2:40am

Wendelius

Comments

Member 8583441 3-Mar-18 10:22am

My problem has not been solved with this solution

Wendelius 3-Mar-18 11:02am

Perhaps you could give more information about the problem. Are you still facing an error or having some other issue?

Wendelius 3-Mar-18 11:08am

You could also go through the following article. It could clarify the way to use Sql objects: Properly executing database operations[^]

Member 8583441 3-Mar-18 10:23am

Sorry Hi Wendelius sir..... I doesn't mention it before saying Hi in the previous comment

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#realJSOP · Accepted Answer · 2018-03-03T02:47:00

I typed this off the top of my head, so it might need some minor tweaking, but this is a more correct way to do this.

C#

public static int ExecuteNonQuery(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
{
    int result = 0;
    if (string.IsNullOrEmpty(connectionString)
    {
        throw new ArgumentNullException("connectionString");
    }

    try
    {
        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            connection.Open();
            using SqlCommand cmd = new SqlCommand(commandText, conn))
            { 
                cmd.CommandType = commandType;
                cmd.Parameters.AddRange(commandParameters);
                result = cmd.ExecuteNonQuery();
            }
        }
    }
    catch (Exception ex)
    {
       // handle the exception here
    }
    return result;
}