Monthly Archives: November 2017

Generate letters with given frequencies in C#

This example generates random letters with the frequencies they have in normal English text. The following code shows how the example gets started. // The letter frequencies. See: // http://en.wikipedia.org/wiki/Letter_frequency private float[] Frequencies = { 8.167f, 1.492f, 2.782f, 4.253f, 12.702f, … Continue reading

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Make a text file a project resource in C#

This is handy for including a large amount of text as a project resource instead of putting the text directly in the code or including a file in the program’s installation package. Open the Project menu and select Properties. Open … Continue reading

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Make a class define and raise events in C#

This example uses a BankAccount class to manage a bank account (and to show how to define and raise events). If the program tries to remove more money from the account than its current balance, the BankAccount object raises an … Continue reading

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Use statement lambdas in C#

The example Use lambda expressions in C# showed how to use lambda expressions to concisely create an anonymous method that takes parameters and returns a value. The following code shows one of the lambda expressions that example used. private void … Continue reading

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Use lambda expressions in C#

Lambda expressions are basically just a shorthand notation for making an anonymous method. There are a couple of formats, the simplest of which has the following syntax. x => expression Here expression is an expression involving the variable x. For … Continue reading

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Use anonymous methods in C#

My previous post Use the predefined Action, Func, and EventHandler delegate types in C# explains how to use the predefined generic Func, Action, and EventHandler delegate types to graph four functions F(x, y). It uses the following code to define … Continue reading

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Use the predefined Action, Func, and EventHandler delegate types in C#

This and the next couple of posts discuss delegates and the somewhat related topics of anonymous methods and lambda expressions. Briefly, delegate types are programmer-defined data types that represent methods. For example, the following code declares a delegate type. // … Continue reading

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A quick note on error messages

I went to a local museum the other day and when the attendant scanned by membership card his computer said: Object not set to a reference of an object. Because we’re programmers, you and I know what that means (more … Continue reading

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Make a button display the picture beneath slightly grayed it in C#

The example Make a button display the picture beneath it in C# shows how to make a button display the picture that lies below it. Unfortunately, the button only adds a border as decoration and the border doesn’t have a … Continue reading

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