public FlatFileColumnCollection(FlatFileToLoad toLoad, bool makeHeaderNamesSane, ExplicitTypingCollection explicitlyTypedColumns, string forceHeaders, bool forceHeadersReplacesFirstLineInFile, string ignoreColumns)
{
_toLoad = toLoad;
_makeHeaderNamesSane = makeHeaderNamesSane;
_explicitlyTypedColumns = explicitlyTypedColumns;
_forceHeaders = forceHeaders;
_forceHeadersReplacesFirstLineInFile = forceHeadersReplacesFirstLineInFile;
_ignoreColumns = ignoreColumns;
}
public DataTable StronglyTypeTable(DataTable workingTable, ExplicitTypingCollection explicitTypingCollection)
{
Dictionary <int, IDecideTypesForStrings> deciders = new Dictionary <int, IDecideTypesForStrings>();
var factory = new TypeDeciderFactory(_culture);
if (!string.IsNullOrWhiteSpace(_explicitDateTimeFormat))
{
factory.Settings.ExplicitDateFormats = new [] { _explicitDateTimeFormat }
}
;
DataTable dtCloned = workingTable.Clone();
bool typeChangeNeeded = false;
foreach (DataColumn col in workingTable.Columns)
{
//if we have already handled it
if (explicitTypingCollection != null && explicitTypingCollection.ExplicitTypesCSharp.ContainsKey(col.ColumnName))
{
continue;
}
//let's make a decision about the data type to use based on the contents
var computedType = new Guesser();
computedType.AdjustToCompensateForValues(col);
//Type based on the contents of the column
if (computedType.ShouldDowngradeColumnTypeToMatchCurrentEstimate(col))
{
dtCloned.Columns[col.ColumnName].DataType = computedType.Guess.CSharpType;
//if we have a type decider to parse this data type
if (factory.IsSupported(computedType.Guess.CSharpType))
{
deciders.Add(col.Ordinal, factory.Create(computedType.Guess.CSharpType)); //record column index and parser
}
typeChangeNeeded = true;
}
}
if (typeChangeNeeded)
{
foreach (DataRow row in workingTable.Rows)
{
dtCloned.Rows.Add(row.ItemArray.Select((v, idx) =>
deciders.ContainsKey(idx) && v is string s?
deciders[idx].Parse(s) :
v).ToArray());
}
return(dtCloned);
}
return(workingTable);
}
