Many options.
1. Classical Rules
In this option, you need an advanced flow rule in import mapping for the attribute in question.
You can hard code the values, if the are not going to change, or put them in a sql table or flat file and read from it.
In the code, you can simply create a select case or if else.
A Sharp snipped of If-Else handing.
If csentry["Location Code"].IsPresent and If !(csentry["Location Code"].Value.Equals (null))
If csentry["Location Code"].Value.toLower="1"
{
mventry["LocationCode"].Value = "CA"
}
else If csentry["Location Code"].Value.toLower="2"
{
mventry["LocationCode"].Value = "NY"
}
.......
.......
.......
else
{
Throw expectation ("This code is not recognized")
//Or Do something else
}
2. Codeless, you can do similar thing with a huge IIF statement.