Solve the binary conversion problem

weiranli00

Convert.FromBase64String (inputValue);
How to convert the value of inputValue to byte []

xyx0312575

Convert byte [] to string Convert.ToBase64String (inputValue);
Convert string to byte [] Convert.FromBase64String (inputValue);

weiranli00

But cmd.Parameters ["@ UserName"]. Value is of type Object

weiranli00

ParameterDirection.Output;

To:

 ParameterDirection.ReturnValue;

I tried it, it seems not possible

lin3412048

Sql's Binay pair receives byte [] to receive
byte [] b = cmd.Parameters ["@ UserName"]. value;

Conversion from byte [] to string requires encoding type
This means that you must be aware of the encoding of the strings stored in the database as binary

Generally there are 2 types: System.Text.Encoding.Default
Or System.Text.Encoding.UTF8

lin3412048

From your code above
Probably all use UTF32

byte [] b = cmd.Parameters ["@ UserName"]. value;
string sUserName = Encoding.UTF32.GetString (b);

weiranli00

byte [] b = cmd.Parameters ["@ UserName"]. value;
string sUserName = Encoding.UTF32.GetString (b);


Error 1 Cannot implicitly convert type "object" to "byte []". There is an explicit conversion (is a cast missing?)

weiranli00

How should the object type be converted to byte [] class? Thank you!

weiranli00

code show as below:
SqlCommand cmd = new SqlCommand ("UsmgcfoxsExict", conn);
cmd.CommandType = CommandType.StoredProcedure;

cmd.Parameters.Add (new SqlParameter ("@ Uid", SqlDbType.Binary, 30));
cmd.Parameters ["@ Uid"]. Value = Encoding.UTF32.GetBytes (paraUid);

cmd.Parameters.Add (new SqlParameter ("@ UserName", SqlDbType.Binary, 30));
cmd.Parameters ["@ UserName"]. Direction = ParameterDirection.Output;

conn.Open ();
cmd.ExecuteNonQuery ();
conn.Close ();

I want to get the value of the parameter "@UserName" in cmd and convert it to string type. The parameter "@UserName" is binary type.

use:
byte [] b = cmd.Parameters ["@ UserName"]. value;
string sUserName = Encoding.UTF32.GetString (b);

But I get the following error:
Error 1 Cannot implicitly convert type "object" to "byte []". There is an explicit conversion (is a cast missing?)

rirgw1

byte [] b = (byte []) cmd.Parameters ["@ UserName"]. value;