connectcode .net barcode sdk Glossar y in .NET

Insert Quick Response Code in .NET Glossar y

// Use a let clause and a nested from clause. using System; using System.Linq; class LetDemo { static void Main() { string[] strs = { "alpha", "beta", "gamma" }; // Create a query that obtains the characters in the // strings, returned in sorted order. Notice the use // of a nested from clause. var chrs = from str in strs let chrArray = str.ToCharArray() from ch in chrArray orderby ch select ch; Console.WriteLine("The individual characters in sorted order:"); // Execute the query and display the results. foreach(char c in chrs) Console.Write(c + " "); Console.WriteLine(); } }

Here, the operator that you are overloading, such as + or /, is substituted for op. The ret-type specifies the type of value returned by the specified operation. Although it can be any type you choose, the return value is often of the same type as the class for which the operator is being overloaded. This correlation facilitates the use of the overloaded operator in expressions. For unary operators, the operand is passed in operand. For binary operators, the operands are passed in operand1 and operand2. Notice that operator methods must be both public and static. For unary operators, the operand must be of the same type as the class for which the operator is being defined. For binary operators, at least one of the operands must be of the same type as its class. Thus, you cannot overload any C# operators for objects that you have not created. For example, you can t redefine + for int or string. One other point: Operator parameters must not use the ref or out modifier.

1,600 =SUM(B2:B5) There is no plug here 80 80 300 =B71 300 =B72 300 =B73 1,060 =SUM(B8:B13) 500 40 540 =SUM(B16:B17) 1,600 =B14+B18 300 300 =B21 300 300 =B24 300 300 =B27 Year 1 250 110 140 =B32-B33 00 00 30 =AVERAGE(B22,B11)*10% 30 =AVERAGE(B25,B12)*10% 30 =AVERAGE(B28,B13)*10% 50 =B34+B36-SUM(B37:B40) 20 =B41*40% 30 =B41-B43

0.00499 0.00645 0.00817 0.01018 0.01246

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website.

1. Select an object and then choose the Interactive Fill Tool (G) from the Toolbox. 2. Click-drag, beginning at one side of your object and dragging to the opposite side at

Both functions will return the product of the variables x and y. However, the generalized, or parameterized, version can be used to return the product of any two numbers, whereas the specific version can be used to find only the product of the global variables x and y.

Another feature lacking in Java is full integration with the Windows platform. Although Java programs can be executed in a Windows environment (assuming that the Java Virtual Machine has been installed), Java and Windows are not closely coupled. Since Windows is the most widely used operating system in the world, lack of direct support for Windows is a drawback to Java. To answer these and other needs, Microsoft developed C#. C# was created at Microsoft late in the 1990s and was part of Microsoft s overall .NET strategy. It was first released in its alpha version in the middle of 2000. C# s chief architect was Anders Hejlsberg. Hejlsberg is one of the world s leading language experts, with several notable accomplishments to his credit. For example, in the 1980s he was the original author of the highly successful and influential Turbo Pascal, whose streamlined implementation set the standard for all future compilers. C# is directly related to C, C++, and Java. This is not by accident. These are three of the most widely used and most widely liked programming languages in the world. Furthermore, at the time of C# s creation, nearly all professional programmers knew C, C++, and/or Java. By building C# upon a solid, well-understood foundation, C# offered an easy migration path from these languages. Since it was neither necessary nor desirable for Hejlsberg to reinvent the wheel, he was free to focus on specific improvements and innovations. The family tree for C# is shown in Figure 1-1. The grandfather of C# is C. From C, C# derives its syntax, many of its keywords, and its operators. C# builds upon and improves the object model defined by C++. If you know C or C++, then you will feel at home with C#. C# and Java have a bit more complicated relationship. As explained, Java is also descended from C and C++. It too shares the C/C++ syntax and object model. Like Java, C# is designed to produce portable code. However, C# is not descended from Java. Instead, C# and Java are more like cousins, sharing a common ancestry, but differing in many important ways. The good news, though, is that if you know Java, then many C# concepts will be familiar. Conversely, if in the future you need to learn Java, then many of the things you learn about C# will carry over. C# contains many innovative features that we will examine at length throughout the course of this book, but some of its most important relate to its built-in support for software components. In fact, C# has been characterized as being a component-oriented language because it contains integral support for the writing of software components. For example,

12/7

agree that they understand the new network topology. This can, in many bridges, take some time to accomplish. The net effect is that in large networks, especially those with ring topologies, the Spanning Tree Protocols can often take more than 1 sec to converge after a failure or a recovery. This is adequate for most customers, but not for all. The most serious problem with the spanning tree algorithms as currently standardized and implemented is the potential for the creation of permanent forwarding loops. When loops occur, bridged frames can circulate forever; each multicast frame, in particular, spews out a copy of itself each time it traverses the loop. If the Spanning Tree Protocol is executed correctly, this is an impossible occurrence. However, if a software bug or hardware failure results in a bridge that sinks, but does not source, the bridge protocol data units (BPDUs) that carry the Spanning Tree Protocol, while allowing that bridge to continue forwarding data frames, also create a permanent loop. These drawbacks to the spanning tree algorithms are well-known in the networking community, and as a result, the spanning tree algorithms have acquired a bad reputation. This is compounded by the lack of good information on these protocols in the available literature (a lack that this chapter is intended to address). All of them, however, have solutions see Using Spanning Tree Effectively and Spanning Tree Alternatives.

11:

1. Do not install more than one radio on a single circuit. If you do, VHF and SSB radios may interfere with each other through their power leads. 2. GPS receivers contain memories that retain coordinates and reduce settling time considerably. Turning off the equipment s power switch does not disconnect the power to the memory, but a drop in voltage may erase the memory. Powering navigation electronics from the house battery rather than the engine-starting battery will help prevent memory loss.