Help me eliminate redundant code
I have an ASP.NET (3.5) page that allows a user to upload an Excel 2003 file with multiple sheets and that data is inserted into staging tables in the database. The mapping of database tables/columns to Excel sheets/columns is specified in an XML file. I use LINQ to SQL to send the data to the database.
ImportTablesDataContext db = new ImportTablesDataContext();
tblImportLoan loan; // class defined by LINQ to SQL
// iterate through each row of data from the Excel worksheet called Loans
foreach (DataRow dr开发者_JAVA技巧 in _data.Tables[ExcelSheetName].Rows)
{
loan = new tblImportLoan();
// iterate through each column in the mapping for the Loans worksheet
foreach (... column in mapping for this worksheet ...)
loan.GetType().GetProperty(column.DBName).SetValue(loan, GetValue(column, dr), null);
db.tblImportLoans.InsertOnSubmit(loan);
}
I repeat most of this code for each of the 5 worksheets. I would like to iterate through the set of 5 tables defined in the mapping - but I cannot figure out how to make the hard-coded class names / methods / properties dynamic (lines 2, 7, and 13 above). This would allow me to avoid referencing the table names outside of the XML file.
Any suggestions?
EDIT: Here is what I'm looking for... but I don't know how to do lines 5 and 8.
foreach (... table in mapping ...)
{
foreach (DataRow dr in _data.Tables[table.ExcelSheetName].Rows)
{
obj = new <LINQ constructor derived from table name>;
foreach (... column in mapping ...)
obj.GetType().GetProperty(column.DBName).SetValue(obj, GetValue(column, dr), null);
db.<LINQ property derived from table name>.InsertOnSubmit(obj);
}
}
I think you could do it by retrieving the Table<TEntity>
objects directly from the DataContext
. First, you need to wrap your code in a generic method:
public void DoWorkFor<TEntity>()
{
ImportTablesDataContext db = new ImportTablesDataContext();
Table<TEntity> table = db.GetTable<TEntity>();
// iterate through each row of data from the Excel worksheet called Loans
foreach (DataRow dr in _data.Tables[ExcelSheetName].Rows)
{
entity = new TEntity();
// iterate through each column in the mapping for the Loans worksheet
foreach (... column in mapping for this worksheet ...)
{
entity.GetType().GetProperty(column.DBName)
.SetValue(entity, GetValue(column, dr), null);
}
table.InsertOnSubmit(entity);
}
}
Then, somewhere else in your program, you need to call this method and supply the appropriate entity type:
DoWorkFor<tblImportLoan>();
DoWorkFor<tblOtherType1>();
DoWorkFor<tblOtherType2>();
DoWorkFor<tblOtherType3>();
DoWorkFor<tblOtherType4>();
Is this close to what you're looking for? Add a comment if not.
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