microstation basics

Canvas BASICS (2) canvas Basics Html section: Part 1 save and restore the drawing statusIn the canvas, the drawing State refers to the complete set of attributes that describe the 2D rendering context appearance at a specific time point, from simple color values to complex transformation matrices and other featuresNote: The current path and the current Bitmap (displayed content) on the canvas are not in th

WinSock network programming BASICS (1) and winsock network programming Basics Record the problems encountered during windows Network Programming and related notes Basic concepts: Socket: Socket originated from UNIX. Socket is an intermediate software abstraction layer for communications between the application layer and the TCP/IP protocol family. It is a set of interfaces. Based on the "open-read/write-Clo

Java basics ----> Java formatting output, java basics ---- formatting In JavaSe5, the printf () format output in C language is introduced. This not only makes the control output code simpler, but also gives Java developers more control over the output format and arrangement. Today, we begin to learn about formatting output in Java. System. out. format () Because the content is relatively simple, we use exam

Java basics --- thread issues, java basics ---1: Inherit the Thread class. Why should we inherit the run method? Answer: Thread implements the Runnable interface, The run method is the Runnable method, and the method in the interfaceThe default value is public abstract. If the Thread class is inherited and the run method is not overwritten, no error is reported, butSet the code for running the thread.2: dif

Java basics --- Servlet filter, basics --- servlet Servlet filters are literally understood as landscape-level filtering to meet the requirements of use. In fact, Servlet filters are the middle layer components of server and client requests and responses, in actual project development, Servlet filters are mainly used to filter browser requests and forward filtered requests to the next resource. Basic concep

Java basics-enumeration details, java basics Enumeration Before JDK1.5, JAVA can define new types in two ways: classes and interfaces. For most object-oriented programming, it seems sufficient to have these two types, but it is not suitable in some special cases. For example, if you want to define a Color class, it can only have three types of Red, Green, and Blue, and other values are incorrect, the enumer

Python basics document string, python basics tutorial String formatting String formatting is implemented using the string formatting operator % Percent. Place a string (formatted string) on the left side of %, and put the value to be formatted on the right side. You can use a value, such as a string or number, you can also use tuples or dictionaries with multiple values, such >>> Print "hello. % s. % s e

Java basics and java Basics In object-oriented programming languages, classes are first-class citizens, and the entire system is composed of classes. Methods in Java cannot exist independently. All methods must be defined in the class. classes or objects must be used as callers for executing methods. The Java language is a static language. After a class is defined, as long as the class file is not re-comp

MySQL BASICS (optimization) and mysql Basics 1. When creating a table, we can set the field width in the table as small as possible to achieve better performance. 2. When possible, set the field to not null as much as possible, so that the database does NOT need to compare NULL values during future query execution. 3. For some text fields, such as "Province" or "gender", we can define them as the ENUM type.

SQL basics 1: SQL Basics 1. What is SQL? SQL is a structured query language. SQL enables us to access databases SQL is an ANSI standard computer language. Ii. What can SQL do? SQL queries for Databases SQL can retrieve data from the database SQL inserts new records into the database SQL updates database data SQL can delete records from the database SQL allows you to create a new database. SQL a

Java basics 6: java BasicsJava basics 61 and javadoc1.1 usage Usage: javadoc [options] [packagenames] [sourcefiles] [@ files] 1.2 instance 1.3 Note To be docized, it must be a public class) Ii. classpath A reference to the classpath variable Iii. Singleton Design Model Iv. inherit the benefits of inheritance 4.1 4.2 Inheritance System 4.3 this and super Super is not a reference

Python basics and python Basics List (similar to array)Note:Any types of elements can exist in the same list.table = ["1","2","3"]; Access the last element:table[-1], Second to lasttable[-2]And so on. Add ElementAdd (append) at the end of the list)table.append(var);Insert an element anywhere)table.insert(index,var);// Add the element var to make its subscript index; Delete an element (del) Sort

JAVA basics 2. java Basics 2.1 keywords Common keywords include: 　　 2.2 identifier In short, an identifier is actually a symbol used to identify something. 　　 2.3 annotation Application Description 　　 Comment: 　　 Annotation application: 　　 2.4 constants and variables Definition and classification of constants 　　 Origin of hexadecimal 　　 Note: byte is 1 byte = 8 binary bits, 1 K = 1024. Basic conversion

Python Study Notes 1-basics and python Study Notes Basics 1) annotations A single line comment starts with #. For example: # The first comment Multi-line comments can contain multiple # numbers, including ''' and "", for example: # Comment on the first line # Comment on the second line ''' Comment on the third line Comment on the fourth line ''' """ Comment on the fifth line Line 6 comment """ 2) lines and

Java basics --- memory analysis, java basics --- Java concurrency isShared Memory Model(Rather than the message passing model), the common state of the program is shared between threads, and the public state in the write-Read Memory is used between threads.ImplicitProceedCommunication. Data Interaction cannot be directly transmitted between multiple threads. Interaction between threads can only be achieved

Java basics 18 and java basics 18 Import java. util. sums; public class Eightheen {/* determines whether a prime number can be divisible by several 9 */public static void main (String [] args) {sums input = new sums (System. in); System. out. println ("enter a prime number:"); int a = input. nextInt (); int B = 9, I = 0; if (judge (a) = 0) {while (B %! = 0) {B = B * 10 + 9; I ++;} System. out. println (a +

Java basics --- reflection mechanism, java basics ---1. Is java a Dynamic Language? Generally speaking, dynamic language means that the program structure or variable type can be changed while the program is running. From this point of view, JAVA and C ++ are not dynamic languages. But JAVA has a very prominent Dynamic correlation mechanism: reflection. Through reflection, Java can load, explore, and use cla

Python BASICS (6): List and metadata, and python Basics I. List The list is a container where a group of data can be placed, and each element in the list has a location index. Each element in the list can be changed. operations on the list will affect the original list. The definition of the List is defined by "[]". elements are separated by commas (,), for example: a = [12,'hello',15.5,True] A list is defi

Python BASICS (4): Conditions and loops, python Basics In actual development, if you want to implement certain functions or requirements, some logic is involved, complicated or simple. How can you implement the python syntax? This involves conditions and loops. Obviously, most languages have conditional and cyclic syntaxes, and python syntaxes are similar to them. It is easy to learn, and students with basi

Python BASICS (10)-numbers, python basics-Numbers The topic of this article is numbers in Python. Describes each numeric type in detail, the various operators they apply, and the built-in functions used to process numbers. At the end of the article, I briefly introduced several modules used to process numbers in the standard library. URL: http://www.cnblogs.com/archimedes/p/python-number.html.Numeric type N