protected override void OnLoadComplete(EventArgs e)
{
if (!IsPostBack && FieldMappings.Count() > 0)
{
LoadFromMappings(true);
}
base.OnLoadComplete(e);
}
protected virtual void Update()
{
this.Validate();
if (this.IsValid)
{
bool shouldNavigate = (Entity.ID == 0);
if (FieldMappings.Count() > 0)
{
LoadFromMappings(false);
}
EasyContext.Entry <ENTITY>(Entity).State = (Entity.ID == 0) ? EntityState.Added : EntityState.Modified;
EasyContext.SaveChanges();
if (shouldNavigate)
{
Response.Redirect(Request.Url.ToString().Split('?').First() + "?id=" + Entity.ID);
}
}
}
protected void LoadFromMappings(bool LoadFields)
{
/*
* The code in this method walks the expression tree and
* maps either the value in the entity into the defined
* control property or pulls the value from the controls
* property into the entity.
*
* This allows us to define the mappings between the entity
* and the controls so that we can create a generic means of
* loading and extracting data from the form.
*
*/
if (FieldMappings.Count() == 0)
{
throw new Exception("No FieldMappings Defined!");
}
foreach (var mapf in FieldMappings)
{
var map = mapf.Body as BinaryExpression;
if (map != null && map.NodeType == ExpressionType.Equal)
{
Expression left = null;
Expression right = null;
#region We can deal with ToString() and also can handle ToString() extension methods
if (map.Left.NodeType == ExpressionType.Call && ((MethodCallExpression)map.Left).Method.Name == "ToString")
{
left = (!((MethodCallExpression)map.Left).Method.IsStatic) ? ((MethodCallExpression)map.Left).Object : ((MethodCallExpression)map.Left).Arguments[0];
}
else
{
left = map.Left;
}
if (map.Right.NodeType == ExpressionType.Call && ((MethodCallExpression)map.Right).Method.Name == "ToString")
{
right = (!((MethodCallExpression)map.Right).Method.IsStatic) ? ((MethodCallExpression)map.Right).Object : ((MethodCallExpression)map.Right).Arguments[0];
}
else
{
right = map.Right;
}
#endregion
if (left != null && left.NodeType == ExpressionType.MemberAccess && ((MemberExpression)left).Member.DeclaringType.IsSubclassOf(typeof(EntityBase)))
{
if (right.NodeType == ExpressionType.MemberAccess)
{
if (LoadFields)
{
RecursiveMemberAccess(((MemberExpression)right), GetValue(map.Left, right.Type, Converters[mapf][1])); //Field <--- Entity
}
else
{
RecursiveMemberAccess(((MemberExpression)left), GetValue(map.Right, left.Type, Converters[mapf][0])); //Field ---> Entity
}
}
else
{
throw new Exception("Feild Mappings must map to a property on a derivative of the System.Web.UI.Control class!");
}
}
else if (right != null && right.NodeType == ExpressionType.MemberAccess && ((MemberExpression)right).Member.DeclaringType.IsSubclassOf(typeof(EntityBase)))
{
if (left.NodeType == ExpressionType.MemberAccess)
{
if (LoadFields)
{
RecursiveMemberAccess(((MemberExpression)left), GetValue(map.Right, left.Type, Converters[mapf][1])); //Field <--- Entity
}
else
{
RecursiveMemberAccess(((MemberExpression)right), GetValue(map.Left, right.Type, Converters[mapf][0])); //Field ---> Entity
}
}
else
{
throw new Exception("Feild Mappings must map to a property on a derivative of the System.Web.UI.Control class!");
}
}
else
{
throw new Exception("Feild Mappings must map to a property on a derivative of the EntityBase class!");
}
}
else
{
throw new Exception("Only == is allowed in feild mappings!");
}
}
}
