Category Archives: internet

Prevent “underlying connection was closed” errors in C#

Posted on May 6, 2020 by RodStephens

This example shows how to fix the error “The underlying connection was closed” when downloading a response from a web page. Background The basic approach for downloading a result from a web page is simple. Create a new WebClient object … Continue reading →

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Get a weather forecast from openweathermap.org in C#

Posted on July 30, 2018 by RodStephens

This example displays a weather forecast from openweathermap.org. To get a forecast or other data, you build a URL describing your request and navigate to it. You then parse the returned XML or JSON data to see what openweathermap.org has … Continue reading →

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Generate a random password in C#

Posted on May 9, 2018 by RodStephens

As I mentioned in a recent post, you should always use a strong password for every login. Remember, a computer can perform millions or billions of operations per second, so your daughter’s birthday or the name of your son’s guinea … Continue reading →

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Why Twitter recently wanted you to change your password

Posted on May 8, 2018 by RodStephens

A few days ago, Twitter asked all of its users to change their passwords. The reason they did that was that they found a bug in their system that made an internal log file store passwords in an unencrypted form. … Continue reading →

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See if the internet is available in C#

Posted on March 1, 2018 by Rod Stephens

There are many ways you can test your network to see if the internet is available. Some methods may indicate that the network is connected if your local network is available even though the internet is not. Even if you … Continue reading →

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Blank the WebBrowser control in C#

Posted on February 4, 2018 by Rod Stephens

If a program displays a web page in a WebBrowser control and then that page become irrelevant to the program, you may want to blank the control. Doing that is as easy as making the control navigate to the special … Continue reading →

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Download and display a text file whenever a program starts in C#

Posted on December 30, 2017 by Rod Stephens

When this example starts, it downloads a file from the internet and displays it. You could do something similar to display a message of the day or announcements for your program. The program uses the following Load event handler to … Continue reading →

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Display the Astronomy Picture of the Day on the desktop in C#

Posted on January 25, 2017 by RodStephens

This example combines the techniques from the following two posts: Download the Astronomy Picture of the Day in C# Set the Windows desktop picture in C# This example uses two settings, LastLoadTime and LastUrl, to determine whether it is a … Continue reading →

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Download the Astronomy Picture of the Day in C#

Posted on January 24, 2017 by RodStephens

Each day the Astronomy Picture of the Day web page does exactly what you would expect: it displays a different astronomy picture. The pictures include planets, nebulae, spacecraft, and other astronomy-related images, and the page includes an explanation of the … Continue reading →

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Map between host names and IP addresses in C#

Posted on January 11, 2017 by Rod Stephens

When you enter a host name and click Go, the program uses the following code to look up the host and display the IP addresses associated with it. using System.Net; … // Display the entered host’s IP address. private void … Continue reading →

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