// Dynamic field titles based on lambda expressions (experimental!)
public static string DynamicFieldTitle(this HtmlHelper html, Expression <Func <object> > expression)
{
object entity;
string fieldName;
if (!ExpressionUtility.TryGetEntityAndFieldNameFromExpression(expression.Body, out entity, out fieldName))
{
throw new ArgumentException("DynamicField expression of unknown type: " + expression.Body.GetType().FullName + "\r\n" + expression.Body.ToString());
}
return(DynamicFieldTitle(html, entity, fieldName));
}
public virtual ActionResult List(string sort, int?show, int?page)
{
var query = EntitiesQuery;
if (sort != null)
{
if (sort.StartsWith("-"))
{
query = ExpressionUtility.ApplyOrderByDescendingClause(query, sort.Substring(1));
}
else
{
query = ExpressionUtility.ApplyOrderByClause(query, sort);
}
}
return(OnList(new PagedList <TEntity>(query, page ?? 1, show ?? 10), sort));
}
public bool FillEntity(NameValueCollection parameters, object entity)
{
foreach (string propName in parameters)
{
MetaColumn column;
if (!Table.TryGetColumn(propName, out column))
{
continue;
}
string propValue = parameters[propName];
ViewData.ModelState().Add(new ModelPropertyState(propName, propValue));
if (propValue == String.Empty && column.ConvertEmptyStringToNull)
{
propValue = null;
}
if (propValue == null && column.IsRequired)
{
string error = column.RequiredErrorMessage;
if (String.IsNullOrEmpty(error))
{
error = String.Format("The field '{0}' is required", column.Name);
}
AddFieldError(column, error);
continue;
}
object value = null;
var fkColumn = column as MetaForeignKeyColumn;
if (fkColumn != null) // For foreign keys, we need to get the parent entity in order to assign it
{
IQueryable parentEntityQuery = ExpressionUtility.ApplyWhereClause(
fkColumn.ParentTable.GetQuery(Context),
fkColumn.ParentTable,
fkColumn.ParentTable.PrimaryKeyColumns[0],
propValue);
value = parentEntityQuery.FirstOrDefault();
}
else if (propValue != null) // Convert it to the correct type for the field
{
TypeConverter converter = TypeDescriptor.GetConverter(column.ColumnType);
try {
value = converter.ConvertFromString(propValue);
}
catch (Exception e) {
AddFieldError(column, e.Message);
continue;
}
}
if (propValue != null)
{
foreach (var validationAttribute in column.Attributes.OfType <ValidationAttribute>())
{
if (!validationAttribute.IsValid(value))
{
AddFieldError(column, validationAttribute.FormatErrorMessage(column.Name));
}
}
}
try {
column.EntityTypeProperty.SetValue(entity, value, null);
}
catch (TargetInvocationException e) {
AddFieldError(column, e.InnerException.Message);
continue;
}
}
return(!HasErrors);
}
