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.net - Converting between SQL char and C#

If I want to insert into a database column of type char(2) from C#. What data type would I use in C#?

If using the following code:

private static SqlParameter addParameterValue(string parameterName, ? parameterValue, SqlCommand command)
    {
        SqlParameter parameter = new SqlParameter(parameterName, SqlDbType.Char);
        parameter.Value = parameterValue;
        command.Parameters.Add(parameter);
        return parameter;
    }

What type would I give to parameterValue?

I already have method like this when the parameterValue is of type string, so this could be a problem when telling the difference between SqlDbType.Char and SqlDbType.Varchar

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char, varchar, nchar, nvarchar are actually strings

the size helps to determine how long the string is...

by the way

char has a fixed length, so if you want to have "1" in a char(2) the contents will be actual "1 "

varchar(2) will be "1"

the n part stands for unicode, so everything inside those fields will be in Unicode.


normally we use nvarchar to save some space on the data, as if you have a char(250) the database will always save the full length, as an empty varchar(250) will be nothing.

In our programming language we then use padding to do what char does, for example, in C#

"1".PadLeft(2);
"1".PadRight(2);

will output " 1" and "1 " respectively.


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