c# .net core barcode generator

c# .net core barcode generator

c# .net core barcode generator

c# .net core barcode generator

c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,
c# .net core barcode generator,

Notice how the method ReplaceSpaces( ) is passed as a parameter Only its name is used; no parameters are specified This can be generalized When instantiating a delegate, you specify only the name of the method to which you want the delegate to refer Of course, the method s signature must match that of the delegate s declaration If it doesn t, a compiletime error will result Next, ReplaceSpaces( ) is called through the delegate instance strOp, as shown here:

We find that, at 3:00 pm, the number of bacteria is B(5) = 10000 17 10

str = strOp("This is a test");

Part I:

Next, strOp is assigned a reference to RemoveSpaces( ), and then strOp is called again This time, RemoveSpaces( ) is invoked Finally, strOp is assigned a reference to Reverse( ) and strOp is called This results in Reverse( ) being called The key point of the example is that the invocation of strOp results in a call to the method referred to by strOp at the time at which the invocation occurs Thus, the method to call is resolved at runtime, not compile time

8 If M(t) is the amount of money in the account at time t then we know that M(t) = 5000 e 4t/100 Here t = 0 corresponds to January 1, 2005 Then, on January 1, 2009, the amount of money present is M(4) = 5000 e 4 4/100 586746

Since version 20, C# has included an option that significantly simplifies the syntax that assigns a method to a delegate This feature is called method group conversion, and it allows you to simply assign the name of a method to a delegate, without using new or explicitly invoking the delegate s constructor For example, here is the Main( ) method of the preceding program rewritten to use method group conversions:

static void Main() { // Construct a delegate using method group conversion StrMod strOp = ReplaceSpaces; // use method group conversion string str; // Call methods through the delegate str = strOp("This is a test"); ConsoleWriteLine("Resulting string: " + str); ConsoleWriteLine(); strOp = RemoveSpaces; // use method group conversion str = strOp("This is a test"); ConsoleWriteLine("Resulting string: " + str); ConsoleWriteLine(); strOp = Reverse; // use method group conversion str = strOp("This is a test"); ConsoleWriteLine("Resulting string: " + str); }

Pay special attention to the way that strOp is created and assigned the method ReplaceSpaces( ) in this line:

The name of the method is assigned directly to strOp C# automatically provides a conversion from the method to the delegate type This syntax can be generalized to any situation in which a method is assigned to (or converted to) a delegate type Because the method group conversion syntax is simpler than the old approach, it is used throughout the remainder of this book

Brad was pleased with his revision It ended up being a lot more concise than the previous version There are now 196 words and fteen sentences, so my average sentence length is just over thirteen words My Empathy Index was good, too I had only two references to myself, but there were eight references to the corporation or the committee members; that s a score of positive six

9 (a)

Although the preceding example used static methods, a delegate can also refer to instance methods It must do so, however, through an object reference For example, here is a rewrite of the previous example, which encapsulates the string operations inside a class called

15:

// Delegates can refer to instance methods, too using System; // Declare a delegate type delegate string StrMod(string str); class StringOps { // Replaces spaces with hyphens public string ReplaceSpaces(string s) { ConsoleWriteLine("Replacing spaces with hyphens"); return sReplace(' ', '-'); } // Remove spaces public string RemoveSpaces(string s) { string temp = ""; int i; ConsoleWriteLine("Removing spaces"); for(i=0; i < sLength; i++) if(s[i] != ' ') temp += s[i]; return temp; } // Reverse a string public string Reverse(string s) { string temp = ""; int i, j; ConsoleWriteLine("Reversing string"); for(j=0, i=sLength-1; i >= 0; i--, j++) temp += s[i]; return temp; } } class DelegateTest { static void Main() { StringOps so = new StringOps(); // create an instance of StringOps // Initialize a delegate StrMod strOp = soReplaceSpaces; string str; // Call methods through delegates str = strOp("This is a test"); ConsoleWriteLine("Resulting string: " + str); ConsoleWriteLine();

1 e x )2

Part I: