ASP.NET Bad Practices: What you shouldn’t do in ASP.NET (Part 4)

I’ve so far covered 15 bad practices in the past three posts and I truly hope that all ASP.NET developers be aware of them including the consequences of each.

Today, I’ll be covering another 5 as the part four.

16. Style Properties on Controls

AVOID

• The four thousand specific control style properties, e.g.
  • EditItemTemplate-AlternateItem-Font-ForeColor-Opacity-Level :S

WHY

• Maintainability
• Bigger page size resulting slower performance since it not being cached

PREFER

• CSS stylesheets

17. Filtering records on app level, not database level

TRY TO AVOID

• Bringing whole list of records from database and filter them on the application level

using (NorthwindEntities ent = new NorthwindEntities())
{  
    var productList = ent.Products.ToList();

    foreach (var product in productList)
    {
        if (product.UnitPrice > 1000)
            Export(product);
    } 
}

WHY

• Unnecessary traffic
• Unnecessary processing resource

DO

• Write proper query (or LINQ Query) to database
• Get only what you need

using (NorthwindEntities ent = new NorthwindEntities())
{  
    var productList = ent.Products.Where(x => x.UnitPrice > 1000).ToList();
    foreach (var product in productList)
    { 
        Export(product);
    } 
}

18. Cookieless Form Auth & Session

DO NOT

• Enable cookieless forms authentication or session

WHY

• It could make your users being the victim to hijacking attacks

DO

• Enable “require cookies” for these features
• Consider using only secure (SSL) cookies for sites serving sensitive information

19. Missing “!IsPostback” check

DO NOT

• Forget the !IsPostBack check if you’re not expecting the execution on every postbacks.
• You can say that, this is so fundamental.
• Yes it is, but I’ve still seen quite couple of developers make this mistake!

protected void Page_Load(object sender, EventArgs e)
{
    //initialize the code here
}

WHY

• Overhead on the unnecessary calls might occurs
• Trigger incorrect / unexpected value

DO

• Understand what you’re really trying to achieve
• Put !IsPostBack check if you’re to only set the value for one first time.

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        //initialize the code here
    }
}

20. Putting Non-common scripts in MasterPages

DO NOT

• Putting unnecessary / non-common scripts / codes in masterpages

WHY

• All pages using the masterpages will be inherited the scripts
• Inappropriate usage may cause inefficiency
• Huge page size

DO

• Put only what really needed to be shared across child pages
• Consider using NestedMasterPages while part of scripts need to be inherited

That’s all for today’s 5 bad practices. Hope that I can compile some more and share with you again in future posts.

See you!