Linq Sequence contains no matching element

Taswar Bhatti March 26, 2010 6 Comments

So sometimes you will get these strange errors or exceptions when using Linq Sequence contains no matching element For example if you use

var result = myEnumerableCollection.First(x => x.Name == person.Name);

1	var result = myEnumerableCollection.First(x => x.Name == person.Name);

This will throw InvalidOperationException with Sequence contains no matching element. But if you use

var result = myEnumerableCollection.FirstOrDefault(x => x.Name == person.Name);
if(result == null)
 //did not find in the collection something went wrong or .....

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var result = myEnumerableCollection.FirstOrDefault(x => x.Name == person.Name);

if(result == null)

//did not find in the collection something went wrong or .....

Which will return you a null if its not found then you can check if the […]

.NET, Misc

.net, FirstOrDefault, LINQ

Asp .NET Redirect To SSL HttpModule

Taswar Bhatti February 18, 2010 4 Comments

There are tones of blog post out there on how to redirect http to https. As in when a user request for http://myserver.com/Login.aspx they will be redirected to https://myserver.com/Login.aspx One can do it with IIS but I find that way a bit ugly since you have to create another site and set the 403 to […]

.NET, ASP .NET

ASP .NET, C#, https, redirect asp .net

Be mindful of the Null Pattern

Taswar Bhatti August 17, 2009 No Comments

Null Pattern Last time I blogged about “Learn the Null Pattern“, but I forgot to mention one thing about the Null Pattern. That is you have to be mindful of it. For example

foreach(var id in IDList)
{
        var employee = db.GetEmployee(id);
	salary = db.CalculateSalary(id);
	employee.Pay(salary);
}

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foreach(var id in IDList)

{

var employee = db.GetEmployee(id);

salary = db.CalculateSalary(id);

employee.Pay(salary);

}

The code looks okay but what if the GetEmployee method actually returns a NullEmployee? Well that would still be okay, since […]

.NET, Design

Design Pattern, Null Pattern

Linq Sequence contains no matching element

Asp .NET Redirect To SSL HttpModule

Be mindful of the Null Pattern

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