Create two array sqlDType and sqlSize
SqlDbType[] sqlDType = new SqlDbType[] {SqlDbType.Int, SqlDbType.Float, SqlDbType.SmallInt, SqlDbType.TinyInt};
int[] sqlSize = new int[] { 4, 8, 2, 1 };
SqlDbType type = SqlDbType.Float;
int iIndex = Array.IndexOf(sqlDType, type);
int iSize = -1;
if (iIndex > -1)
iSize = sqlSize[iIndex];