1. C# tutorial

  • 1.1. C# introduction

    C# is a simple, modern, general-purpose, object-oriented programming language developed by Microsoft and approved by Ecma an...
    2025-10-25 13:34:35 UTC
  • 1.2. C# environment

    In this chapter, we will discuss the tools needed to create C# programming. We have already mentioned that C# is .Net pa...
    2025-10-25 13:34:37 UTC
  • 1.3. C# program structure

    Before we learn the basic building blocks of the C# programming language, let’s take a look at the smallest program structur...
    2025-10-25 13:34:35 UTC
  • 1.4. C# basic syntax

    C# is an object-oriented programming language. In the object-oriented programming method, the program consists of a variety ...
    2025-10-25 13:34:36 UTC
  • 1.5. C# data type

    In C#, variables are divided into the following types: Value type Reference type Pointer type 1.5.1. Valu...
    2025-10-25 13:34:41 UTC
  • 1.6. C# type conversion

    Type conversion is fundamentally type casting, or the conversion of data from one type to another. In C#, there are two form...
    2025-10-25 13:34:43 UTC
  • 1.7. C# variable

    A variable is simply the name of a storage area for the program to operate on. In C#, each variable has a specific type, whi...
    2025-10-25 13:34:39 UTC
  • 1.9. C # operator

    An operator is a symbol that tells the compiler to perform a specific mathematical or logical operation. C # has a wealth of...
    2025-10-25 13:34:36 UTC
  • 1.10. C # judgment

    The judgment structure requires the programmer to specify one or more conditions to be evaluated or tested, as well as state...
    2025-10-25 13:34:41 UTC
  • 1.11. C # if statement

    One if a statement consists of a Boolean expression followed by one or more statements. 1.11.1. Grammar # In C ...
    2025-10-25 13:34:36 UTC
  • 1.12. C# if...else statement

    One if statement can be followed by an optional else statement else statement is executed when the Boolean expre...
    2025-10-25 13:34:42 UTC
  • 1.13. C# nesting if statement

    In C #, nesting if-else statement is legal, which means that you can use a if or else if use another within th...
    2025-10-25 13:34:39 UTC
  • 1.14. C # switch statement

    One switch statement allows you to test when a variable is equal to multiple values. Each value is called a case and...
    2025-10-25 13:34:40 UTC
  • 1.15. C # cycle

    Sometimes, you may need to execute the same piece of code multiple times. Ingeneral, statements are executed sequentially: t...
    2025-10-25 13:34:38 UTC
  • 1.16. C # while loop

    As long as the given condition is true, the while loop statement repeats a target statement. 1.16.1. Grammar # ...
    2025-10-25 13:34:38 UTC
  • 1.17. C # for/foreach loop

    One for loop is a repetitive control structure that allows you to writea loop that executes a specific number of times. ...
    2025-10-25 13:34:40 UTC
《地理信息系统原理、技术与方法》  97

最近几年来,地理信息系统无论是在理论上还是应用上都处在一个飞速发展的阶段。 GIS被应用于多个领域的建模和决策支持,如城市管理、区划、环境整治等等,地理信息成为信息时代重要的组成部分之一; “数字地球”概念的提出,更进一步推动了作为其技术支撑的GIS的发展。 与此同时,一些学者致力于相关的理论研究,如空间感知、空间数据误差、空间关系的形式化等等。 这恰好说明了地理信息系统作为应用技术和学科的两个方面,并且这两个方面构成了相互促进的发展过程。