Determining file suitablility before uploading using HTML5 File API

Determining file suitablility before uploading using HTML5 File API

Today I wanted to write about HTML5’s File API. In the past, a developer would generally write code to determine if a file type was appropriate after the file had been uploaded. This would quite often be annoying for a user especially if the file was large and they only find out that it is inappropriate after it has finished uploading. Now, using the File API, the web page can determine if a file is acceptable before the user uploads it. In fact, not only can you gather the file type but you can find out other information about a file before committing to upload, such as the file size

Project planning using the time-boxing method

Project planning using the time-boxing method

Quite often in the lifetime of a product’s development something unexpected will happen that will throw your project plan out of the window and you will have to reorganise your resources respectively. This could be the customer changing their mind on some included functionality, adding additional requirements or the priority of requirements. In this article I will continue the development journey with project planning using a time-boxing method to make sure everyone stays on schedule, interruptions are minimised and the customer gets what is most important to them. I actually wrote this back in April but didn’t publish as I thought it could do with some graphics to break up

Location aware content in your HTML5 web page

Location aware content in your HTML5 web page

I know this is not very spooky post for Halloween. Unless, of course, you were sitting there this evening thinking to yourself, I wonder how you make a web page location aware and happened across my post. Anyway, back to the subject. Using HTML 5 you can now include the user’s location within your application. The Geolocation API was included in HTML5 although not strictly as part of the HTML5 specification. You can now use the power of a location aware device to know where your user is and provide content relevant to them. It is quite simple to do and this article explains the code that you need to

Working with large data sets in Excel powered ASP.NET websites

Working with large data sets in Excel powered ASP.NET websites

Working with large amounts of data can be slow going using Microsoft Excel’s internal lookup functions which is amplified if you are publishing lookup results on the internet dynamically. In this example, I have created a large(ish) table of sales data that I want to be able to pick from using some specified criteria. All of the information in this table is dummy data and even the specified criteria are probably not what a sales manager would be looking for. The purpose of this data is to show that handling large data sets is best accomplished outside of Excel especially if you want to display it on the web. This

Cookieless user data storage using HTML5 Web Storage API

Cookieless user data storage using HTML5 Web Storage API

A while back I started writing about HTML5 and wrote “a brief guide to the enhancements and new features of HTML5” as well as more detailed articles about “HTML5 Video“, drawing using the “HTML5 Canvas” and “HTML5 Canvas Animation” and also one about scaleable vector graphics (SVG) with examples using HTML5. This follows on from those subjects with an article dedicated to the “HTML5 Web Storage API”. There are two new types of web storage that are now available to web developers in HTML5 for both local and session storage. However, before I can cover the Web Storage API, I think it’s best to cover what there was before HTML5

Working with charts in Excel powered ASP.NET websites

Working with charts in Excel powered ASP.NET websites

Personally, I think Microsoft Excel charts are powerful and look quite good so in this article, we will use SpreadsheetGear to connect to a workbook and fetch a chart as an image to display on an APS.NET web page. Obviously websites could use a charting library or define their own chart like images using the data generated from Excel but in this example we will get the image of a chart that is generated in Excel. This article is part of a set on using SpreadsheetGear to include the power of Microsoft Excel behind your website. This article does not cover the basics of using SpreadsheetGear so if you are

Working with macro functions in Excel powered ASP.NET websites

Working with macro functions in Excel powered ASP.NET websites

In this article, we will use SpreadsheetGear to connect to a macro-enabled workbook that has one user-defined macro function and we will attach a class to the SpreadsheetGear object to replace that function at runtime. This is not just a feature of SpreadsheetGear as middle-wear between a website or application and a Microsoft Excel workbook will not support macros but some of them such as SpreadsheetGear will allow you some way of redefing them. We will populate the initial page values of an ASP.NET website from a spreadsheet, make changes to those values on the website and get the results from a macro-enabled workbook. The workbook uses a custom function

How to build Microsoft Excel powered ASP.NET websites

How to build Microsoft Excel powered ASP.NET websites

Microsoft Excel provides easy to use and very good (in my opinion) functionality for most business applications and with its charting capabilities and extensibility through Visual Basic for Applications (VBA) and data links to other storage applications it gives you a powerful tool at your fingertips on your desktop or laptop. That is great if you are with your client or don’t mind sending them your Workbook to use on their machines but it’s not very practical if you want to protect your intellectual property or view on different devices such as tablets or smart phones. Sharing your tools online legitimately has always been a challenge but using various components

Creating and using scalable vector graphics on the web

Creating and using scalable vector graphics on the web

This article is about Scalable Vector Graphics (SVG) on your web pages. I would have classed it as a HTML 5 tutorial but it is not strictly speaking to do with HTML 5 although it does use HTML to display the images. An SVG is a file that has been written in XML and contains all of the information needed to draw the image on the screen in text. This way the browser knows exactly how to re-scale it depending on the viewing area so there is no loss of quality when viewing on a small or large screen. You can of course create graphics using the HTML 5 Canvas

Animation example using the HTML 5 Canvas

Animation example using the HTML 5 Canvas

Following on from my article Getting started with HTML5 canvas, this short article adds another example of what you can do. If you haven’t already done so, it is worth revisiting my previous article to get familiar with the terms and Canvas setup. This article shows you that animation on the HTML 5 Canvas is really quite simple. The example here moves a small box around the screen and changes its direction and colour when it hits the boundary of the canvas. As there is not much to it so this brief article will include the full code, a couple of screenshots and explain what is happening. HTML 5 Code