public override bool IsValid(object value)
{
// Construct the data context
//ConstructorInfo constructor = DataContextType.GetConstructor(new Type[0]);
//DataContext dataContext = (DataContext)constructor.Invoke(new object[0]);
var repository = DependencyResolver.Current.GetService(DataContextType);
var data = repository.GetType().InvokeMember("GetAll", BindingFlags.Instance | BindingFlags.InvokeMethod | BindingFlags.Public, null, repository, null);
// Get the table
//ITable table = dataContext.GetTable(EntityType);
// Get the property
PropertyInfo propertyInfo = EntityType.GetProperty(PropertyName);
// Our ultimate goal is an expression of:
// "entity => entity.PropertyName == value"
// Expression: "value"
object convertedValue = Convert.ChangeType(value, propertyInfo.PropertyType);
var rhs = Expression.Constant(convertedValue);
// Expression: "entity"
var parameter = Expression.Parameter(EntityType, "entity");
// Expression: "entity.PropertyName"
var property = Expression.MakeMemberAccess(parameter, propertyInfo);
// Expression: "entity.PropertyName == value"
var equal = Expression.Equal(property, rhs);
// Expression: "entity => entity.PropertyName == value"
var lambda = Expression.Lambda(equal, parameter).Compile();
// Instantiate the count method with the right TSource (our entity type)
MethodInfo countMethod = QueryableCountMethod.MakeGenericMethod(EntityType);
// Execute Count() and say "you're valid if you have none matching"
int count = (int)countMethod.Invoke(null, new object[] { data, lambda });
return(count == 0);
}
public override bool IsValid(object value)
{
string str = (string)value;
if (String.IsNullOrWhiteSpace(str))
{
return(true);
}
// Cleanup the string
str = str.Trim();
// Construct the data context
ConstructorInfo constructor = DataContextType.GetConstructor(new Type[0]);
DataContext dataContext = (DataContext)constructor.Invoke(new object[0]);
// Get the table
ITable table = dataContext.GetTable(EntityType);
// Get the property
PropertyInfo propertyInfo = EntityType.GetProperty(PropertyName);
// Expression: "entity"
ParameterExpression parameter = Expression.Parameter(EntityType, "entity");
// Expression: "entity.PropertyName"
MemberExpression property = Expression.MakeMemberAccess(parameter, propertyInfo);
// Expression: "value"
object convertedValue = Convert.ChangeType(value, propertyInfo.PropertyType);
ConstantExpression rhs = Expression.Constant(convertedValue);
// Expression: "entity.PropertyName == value"
BinaryExpression equal = Expression.Equal(property, rhs);
// Expression: "entity => entity.PropertyName == value"
LambdaExpression lambda = Expression.Lambda(equal, parameter);
// Instantiate the count method with the right TSource (our entity type)
MethodInfo countMethod = QueryableCountMethod.MakeGenericMethod(EntityType);
// Execute Count() and say "you're valid if you have none matching"
int count = (int)countMethod.Invoke(null, new object[] { table, lambda });
return(count == 0);
}
