在MVC ASP.net中使用X-editable时不要重复自己的最佳方法

Question

I have just started using a nice js library to edit form elements in place. Here is the link for the library.

It works well that you can just right in place update your form elements. However you will need to create an action for each individual form element.

An example :

<a href="#" class="EditableSection" data-type="text" data-pk="@Model.id" data-name="Name" data-url="@Url.Action("_EditName", "User", new { Model.id})" data-title="Edit Name">@Model.Name</a>

<a href="#" class="EditableSection" data-type="text" data-pk="@Model.id" data-name="MiddleName" data-url="@Url.Action("_EditMiddleName", "User", new { Model.id})" data-title="Edit Middle Name">@Model.MiddleName</a>

<a href="#" class="EditableSection" data-type="text" data-pk="@Model.id" data-name="SurName" data-url="@Url.Action("_EditSurName", "User", new { Model.id})" data-title="Edit SurName">@Model.SurName</a>

In UserController I believe that I will need to have 3 different actions for each and most of the inside of the action similar apart from the the element which gets updated.

here is one of the actions :

        [HttpPost]
        public ActionResult _EditUserName(int id, int pk, string value, string name)
        {

            var user= this._userRep.First(o => o.id== pk);
            if (user!= null && user.id== id)
            {
                if (!string.IsNullOrEmpty(value))
                {

                    user.UserName= value; //this is the only line changes from one to another action respectively   user.MiddleName = value or user.SurName = value 

                    this._userRep.Update(user);
                    this._userRep.SaveChanges();
                    return new HttpStatusCodeResult(HttpStatusCode.OK);
                }
                return Json(new { status = "error", msg = "You cannot leave blank" });

            }

            return  Json(new {status="error",msg="You cannot leave blank"});
        }

I can see 2 options to improve make the code DRY.

First one is create one action for each form element and put all the common task in a separate method to call on each action. (Still I believe too much typing and mess)

Second option what I focus on but I could not figure it out which I would like to get your help here :

Create a common action as _EditUserDetails and use condition something below :

        [HttpPost]
        public ActionResult _EditUserDetails(int id, int pk, string value, string name)
        {

            var user= this._userRep.First(o => o.id== pk);
            if (user!= null && user.id== id)
            {
                if (!string.IsNullOrEmpty(value))
                {

                  if(name=user.UserName.toString())
                    user.UserName= value; 
                  else if(name=user.MiddleName.toString())
                      user.MiddleName= value; 
                  else if(name=user.MiddleName.toString())
                   user.SurName= value; 

                    this._userRep.Update(user);
                    this._userRep.SaveChanges();
                    return new HttpStatusCodeResult(HttpStatusCode.OK);
                }
                return Json(new { status = "error", msg = "You cannot leave blank" });

            }

            return  Json(new {status="error",msg="You cannot leave blank"});
        }

I cannot get the name of the user object variable name for the comparison and also I am not sure this is the correct way of checking it .

if(name=user.UserName.toString()) // name is equal to form element name. and I know user.UserName.toString() returns the value instead of 'UserName'

here is instead of user.UserName value I just would like to use the name itself which is UserName for the comparison? I can create a static strongly typed class to use in this conditions but do you think this is necessary? why I cannot just use the name of the object variables for comparison?

What would be your best practise for this?

Answer 1

You can user reflection to set the property value based on the name. If you use this approach I would advise you to add a white list to prevent over posting.

<a href="#" class="EditableSection" data-type="text" data-pk="@Model.id" id="Name" data-url="@Url.Action("InlineEdit", "User", new { Model.id})" data-title="Edit Name">@Model.Name</a>

<a href="#" class="EditableSection" data-type="text" data-pk="@Model.id" id="MiddleName" data-url="@Url.Action("InlineEdit", "User", new { Model.id})" data-title="Edit Middle Name">@Model.MiddleName</a>

xeditables passes the ID through in the name parameter so no need to add a "data-name" attribute

    [HttpPost,
    ValidateAntiForgeryToken]
    public ActionResult InlineEdit(int pk, string value, string name)
    {
        //
        // White list to prevent overposting
        string whitelist = "Name,MiddleName,SurName";
        if (!whitelist.Contains(name))
        {
            return new HttpStatusCodeResult(HttpStatusCode.BadRequest, string.Format("Invalid Field {0}", name));
        };

        var user= this._userRep.First(o => o.id== pk);;
        if (user == null)
        {
            return new HttpStatusCodeResult(HttpStatusCode.BadRequest, string.Format("Resource not found"));
        }
        try
        {
                this.SetPropertyValue(user, name, value);
                this._userRep.Update(user);
                this._userRep.SaveChanges();
                return new HttpStatusCodeResult(HttpStatusCode.OK);
        }
        catch (DbEntityValidationException ex)
        {
            var error = ex.EntityValidationErrors.First().ValidationErrors.First();
            this.ModelState.AddModelError(error.PropertyName, error.ErrorMessage);
            return new HttpStatusCodeResult(HttpStatusCode.BadRequest, string.Format("{0}: {1}", error.PropertyName, error.ErrorMessage));
        } 
    }

Here is a function to set the property before converting it to the appropriate data type

    private Object SetPropertyValue(Object entity, string property, string value)
    {
        PropertyInfo propertyInfo = entity.GetType().GetProperty(property);

        if (propertyInfo != null)
        {
            Type t = propertyInfo.PropertyType;
            object d;
            if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable<>))
            {
                if (String.IsNullOrEmpty(value))
                    d = null;
                else
                    d = Convert.ChangeType(value, t.GetGenericArguments()[0]);
            }
            else if (t == typeof(Guid))
            {
                d = new Guid(value);
            }
            else
            {
                d = Convert.ChangeType(value, t);
            }

            propertyInfo.SetValue(entity, d, null);
        }
        return entity;
    }

A lot of code for three fields (I would rather user 3 actions in that case). Very useful if you have a lot of fields you want to update.