Sort datatable with the Select method when column names contain commas

Well, basically, you can't do it.
I am looking at the internal ParseSortString(string sortString) in the DataTable object of NET 1.1, where the first thing the method does is to split the string by commas, then check for square brackets. This insures that there is no way to sort datatables by columns with commas in their names. The funny thing is that the filtering expression is treated like royalty by an ExpressionParser object, and allows column names with commas inside.
Now let's check the code for NET 2.0. It's identical.

The solution is a little annoying code like this:

private DataRow[] SelectSafe(DataTable dt, string filter, string sort)
{
  var columns = new string[dt.Columns.Count];
  for (var c=0; c<dt.Columns.Count; c++)
  {
    columns[c] = dt.Columns[c].ColumnName;
    if (dt.Columns[c].ColumnName.IndexOf(',')>-1)
    {
      dt.Columns[c].ColumnName = dt.Columns[c].ColumnName.Replace(',', ';');
      // assume that the column name was bracketed correctly in the select
      sort = sort.Replace(
        "[" + columns[c] + "]",
        "[" + dt.Columns[c].ColumnName + "]");
    }
  }
  var dr = dt.Select(filter, sort);
  for (int c=0; c<dt.Columns.Count; c++) {
    dt.Columns[c].ColumnName = columns[c];
  }
  return dr;
}

I am sure there is more elegant code, but this seems to be the only solution so far except manually sorting a DataTable.

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MSDN Briefing Bucharest 24th of October 2006

The whole meeting took place at the Titulescu room at RomExpo. They had 4 desks that spanned the alphabetical ordering of software firms participating, so the entry was really comfortable. They gave us a pen and a little notebook to take notes, too. The whole meeting lasted from 9:00-16:30, then there was an hour of free talks.
My general impression of the briefing was good. The presenters were enthusiastic and talked about: application development on Windows Vista with NET 3.0 and Sharepoint and Office 2007. The new Microsoft XML office format was presented, programatic methods of accessing and creating them, how to mix Sharepoint and Office in order to create quick Excel based web sites, etc. The most interesting part, though, was of course the last. It presented the advances in programming technology like the C# 3.0 features and ADO.Net vNext. Too bad I've already read about those technologies, but the enthusiastic presentation mode (alas, SPOKEN TOO LOUD) was refreshing.
The information was as compacted as possible, but there was too little code for me, even if most presenters seemed to have the same hatred for marketing slides as I did.
There were also 30 minutes of coffee break and 1 hour of lunch. The lunch food was very good and varied, from chinese apetizers like sesame meatballs and Shanghai chicken to sandwiches, salads and sweets. Taking into account that I've been to a similar Microsoft thing in Milano, where they barely gave us some sandwiches in plastic bags, this was truly great.

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NullReferenceException in GridView BuildCallbackArgument when trying to render it dynamically with paging

Whoa! Big title there. This article applies to errors in ASP.NET 2.0 when trying to dynamically render a gridview with paging.

I have been trying to "Ajaxify" my web programming and I've found that the easiest method is to wrap everything I need in Web User Controls, render the controls, then send the rendered string through ajax to fill some innerHTML.
Well, the fine people at Microsoft thought otherwise. I have been trying to render a web user control with a gridview inside it for 3 hours now and nothing helped. I kept getting a NullReferenceException when calling GridView.DataBind and the StackTrace showed it originated in the BuildCallBackArgument(int) method.
Nothing helped except actually decompiling the code of the GridView itself. I've found out that it called a method in the Page of the control, in other words it needed a page. I gave it a page, but then another problem occured that I'd already solved here. I already had a parent page that overrode the offending method, so the final code is this:

ParentPage pp=new ParentPage();  // where ParentPage is a Page with VerifyRenderingInServerForm(Control control) overriden so it doesn't do anything
pp.EnableEventValidation = false; //another silly error
uc.Page = pp; //uc is the user control needing rendering
uc.Bind();

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Bush in space.

It just had to come. It was inevitable. Bush has signed a "tough space policy" which basically says the US will hold space itself hostage as they do water, air and economy on Earth.
Just read the BBC article and draw your own conclusions. Before they even explore it, the Americans seize space as their own, all in the name of "protecting" their space sattelites or whatever.
So next time you god damned university students want to launch your geek science projects into space, you'd better clear it with Bush. Or Rumsfeld.

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Javascript replace function

Unlike .NET C# (or most other programming languages), the Javascript replace function only replaces the first instance of a string. To replace all the instances, you need to use regular expressions.
Simon Willison's Weblog contains a good article on this.

Basically, if you use str1.replace(str2,str3) it will return str1 with the first occurence of str2 replaced with str3. If you use str1.replace(regexp1,str3) and the regular expression has the g modifier it will return str1 with all matches of regexp1 replaced with str3.

A regular expression looks like : /searchpattern/modifiers.
You can create a regular expression from a string by using the

new RegExp(str2,modifiers)

syntax.

The problem comes when you want to create a regular expression from a variable that may contain regular expression escape sequences. Here is Simon Willison's function that "escapes" the string in order to use the RegExp syntax safely, slightly modified to contain the '^' character:

RegExp.escape = function(text) {
  if (!arguments.callee.sRE) {
    var specials = [
      '/', '.', '*', '+', '?', '<', '>',
      '(', ')', '[', ']', '{', '}', '\\', '^'
    ];
    arguments.callee.sRE = new RegExp(
      '(\\' + specials.join('\\') + ')', 'g'
    );
  }
  return text.replace(arguments.callee.sRE, '\\$1');
}

Example: str=str.replace(/\\/g,'\\\\') (replace slashes with double slashes)

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Oh, come on!

This is an image from the BBC web site and the title of the BBC article is Rice launches Korea crisis tour and the caption is Japan and the US pledge to work on implementing sanctions on North Korea, the US Secretary of State says.
I knew politicians are assholes, but how can you smile like that while deciding pledging to impose sanctions on some other nation? Look at her! You'd say she's hugging her daughter while petting the cutest cat ever. And she's imposing sanctions! And the title sounds like she has just opened a tourist resort. That whole picture is wrong. Geez!

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Checking your web app against different browser resolutions

I have found three basic methods:

1. Use an online type of viewer.
   You select the resolution, type in the URL of your site, then sit back and relax.
   I see a lot of problems for this method:
   
   • you don't want everybody to know you are working on a site
   
   
   • you don't want the site to be open to the public while you work on it
   
   
   • you need an internet connection
   
   


2. Use an external program.
   BrowserSizer is as good as any. It's free and easy to use. You select the resolution and it resizes your IE window accordingly.
   The only problem I see is that you need the program. You install it, it messes with your browser settings, etc.


3. Use a javascript script in the IE addressbar:
   

   javascript:db=document.body;bst=db.style.zoom=1;rd=prompt("Width:",800);
   db.style.zoom=db.offsetWidth/rd;void('')

   
   Unfortunately, the zoom messes up quite a few things, including fixed table headers or custom javascript controls. However, I do believe it is the best solution for most situations.
   

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