Monday, 23 November 2009
Rounded Corners with JQuery the Painless Way
http://code.google.com/p/jquerycurvycorners/downloads/list
It's this easy. Let's say you want all divs with the css class of rounded to have rounded corners. You just add this: $("div.rounded").corner(); inside the document.ready block.
Friday, 13 November 2009
Adding User Controls programmatically
Scenario
You have a view product page in a shopping cart application which has an "add to cart" button which adds one of these products to a shopping basket.
Your client comes along and says they want users not to have to drill down to the product detail page to add products to their baskets. So you are
now faced with having to work out how you will add an add to cart button to each product summary. Here's how you could deal with this problem.
1. Create a user control which displays a product summary and maybe call it something like displayProduct.ascx
2. User Controls are classes so expose a property or properties within the code behind file
For example let's say your Product Class has an ID property you could set your user control to have a productID property like this:
Private _productID As Integer
Public Property productID() As Integer
Get
Return _productID
End Get
Set(ByVal value As Integer)
_productID = value
End Set
End Property
2.a. take the add to cart button functionality from your product detail page and replicate it in your user control. So you might add a button called
AddToCart and code something like:
Protected Sub AddToCart_Click(ByVal sender As Object, ByVal e As System.Web.UI.ImageClickEventArgs) Handles AddToCart.Click
Dim c As New Cart
Dim p As New Product
p = p.GetProductByID(me._productID)
c.AddProductToCart(p)
.... etc
End Sub
3. Add a placeholder control to your new product listings page to contain the user controls.
4. Now for the clever bit, let's say you have a ProductManager class which returns a list of Product class instances which you can pass into your
user controls, you can then loop through this list and add a displayProduct.ascx user control for each Product in your list. The code might look something
like this:
Public Sub DisplayHandsets()
Dim pm As New ProductManager
Dim pl As New List(Of Product)
pl = pm.GetProducts
Dim p As Product
For Each p In pl
'add user control for each product
Dim dp As displayProduct = CType(LoadControl("displayProduct.ascx"), displayProduct)
dp.productID = p.ID
' add the user control to your placeholder
phProducts.Controls.Add(dp)
Next
End Sub
5. Give yourself a big pat on the back for doing some serious nerd kung fu!
Regular Expressions 101 Part Two
In the previous post in this series we looked at a simple example of a regular expression:
^\d*$
which restricts input to either none or any number of digits.
The table below outlines a few slightly more complex variations of this regular expression and in which instances they would be valid.
"yes" means that particular number of digits would be valid input.
Quantity of numerical characters | + | * | {2} | {2,3} |
---|---|---|---|---|
Regular Expression | ^\d+$ | ^\d*$ | ^\d{2}$ | ^\d{2,3}$ |
0 | yes | |||
1 | yes | yes | ||
2 | yes | yes | yes | yes |
3 | yes | yes | yes | |
4 | yes | yes |
So to break this down "+" means one or more instances of the "pattern" specified
by the regular expression is required; "*" means none or any quantity of the
pattern need to be present; "{2}" means the length must be 2 instances of the
specified pattern; {2,3} means there must be either 2 or 3 instances of the
pattern present.
- . - any character
- ? - optional i.e. there can be either none of these or any other quantity
- + - at least one or more
- * - none or any quantity
You can also specify groups of characters to be matched by a regular expression. For example:
([A-Z][a-z]) specifies that the pattern must start with a Capital letter followed by a lower case character.Clear as mud eh ;)
Tuesday, 10 November 2009
Regular Expressions 101 Part One
So here's an example regular expression:
^\d{2}$
This would restrict input to numeric values only and two characters maximum length.
^ = start
\d = numbers only
{2} = how many
$ = end
There is a very useful regular expression testing tool here
Let's say you want numbers only i.e. no numbers or only numbers.
^\d*$