private string GetLineFromModel(T row)
{
var line = string.Empty;
foreach (var field in layout.GetOrderedFields())
{
var modelProperty = typeof(T).GetProperty(field.PropertyInfo.Name);
if (modelProperty != null)
{
var modelValue = modelProperty.GetValue(row).ToString();
// Throw exception on truncation. Early failure preferable to incorrect data.
// e.g. 1.234567890E+100 would truncate to 1.234 @ 5 char field length.
// TODO: Accept a type converter here for writes
if (field.Length < modelValue.Length)
{
throw new Exception($"Field is too short for value. '{field.PropertyInfo.Name}' field length of {field.Length} " +
$"is less than required length of {modelValue.Length} for value {modelValue}");
}
var valueForFile = modelValue
.Substring(0, Math.Min(field.Length, modelValue.Length))
.PadRight(field.Length);
line += valueForFile;
}
else
{
throw new Exception($"Model property with name {field.PropertyInfo.Name} was not found.");
}
}
return(line);
}
public FixedWidthFileWriter(IFlatFileLayoutDescriptor <T> layout, string filePath)
{
this.layout = layout;
this.filePath = filePath;
if (layout.GetOrderedFields()
.Any(x => x.TypeConverter == null))
{
throw new ArgumentException("Missing TypeConverter for one or more fields", nameof(layout));
}
}
/// <summary>
/// For each field in layout, the field is extracted from row and added to model (TEntity)
/// </summary>
/// <exception cref="T:Exception">Property name is null, not unique, or not found in TEntity.</exception>
/// <param name="row"></param>
/// <returns></returns>
private T GetModelFromLine(string row)
{
var model = new T();
foreach (var field in layout.GetOrderedFields())
{
if (field.ShouldSkip)
{
continue;
}
// This could throw ambigous match exception if inheritance is used on the model incorrectly (e.g. new
// keyword missing, and hiding a parent property)
// This could throw argument null exception if Field or PropertyInfo or Name are null
// Should check for these conditions eventually.
var modelProperty = typeof(T).GetProperty(field.PropertyInfo.Name);
if (modelProperty != null)
{
var stringToConvert = row.Substring(field.StartPosition, field.Length);
var typeConverter = field.TypeConverter;
var convertedValue = typeConverter.GetConvertedValue(stringToConvert);
modelProperty.SetValue(
model,
convertedValue);
}
else
{
/* Model type (TEntity) of LayoutDescriptor and FixedWidthFileParser must match, so
* short of user monkeying around with the PropertyInfo, the layout descriptor's
* field.PropertyInfo.Name should always be found in the model */
throw new Exception($"Model property with name {field.PropertyInfo.Name} was not found.");
}
}
return(model);
}
