[C learning notes] C language realizes Pos(), Copy(), Delete() functions of Delphi

This code was originally created by blogger Huang Renlai. For reprint, please indicate the source: https://blog.csdn.net/weixin_43334745 2018-10-05  Recently, I am learning C, deeply aware of the power (and danger) of the C pointer. If I master it well, I will control the memory like a fish in water; if I master it badly, I ...

Posted by Jeb. on Fri, 20 Dec 2019 18:00:49 +0100

Delphi basic (constant, set, array [dynamic array, multidimensional array])

I. constant 1. Constant definition: the value defined at the beginning is not allowed to be changed during the operation of the program 1 const 2 pi: Double = 3.141592; / / defined as constant 3 {constant can be defined without type declaration. Compiler will determine the type of constant} according to specific value 4 Pi2 = 3.1415;   2. ...

Posted by jarvishr on Mon, 09 Dec 2019 04:23:25 +0100

App Alipay payment

1. Transfer payment process: Step 1: create an app and get APPID Open platform to ant golden clothing( open.alipay.com )To create an application in the developer center, an app unique ID (APPID) will be generated and the payment function will be applied for.. Step 2: configure the key The Alipay public key: Alipay's RSA public key. The ...

Posted by subesc on Mon, 04 Nov 2019 18:53:24 +0100

Delphi - Call an external program and block it into an external program

Delphi calls external programs and blocks them into external programs Background note: Some time ago, a data conversion system was developed. The business logic stated that the data needed to be compressed into. tar.gz format. I use Windows system, Mr. batch file processing, and then call WinExec to execute batch file, sleep and wait for a p ...

Posted by ecxzqute on Fri, 04 Oct 2019 04:09:10 +0200

System V message queue

Catalog 1. overview 2. Message queue API msgget msgsnd msgrcv msgctl 3. Simple procedures code implementation common.h msgcreate.c msgsnd.c msgrcv.c msgrmid.c Code testing 1. overview System V message qu ...

Posted by cytech on Wed, 18 Sep 2019 16:41:56 +0200

day1 job 2: multi-level menu operation

Assignment 2: Multilevel menu (1) Three-level menu (2) You can choose to enter each sub-menu at the next time. (3) Necessary New Knowledge Points: Lists, Dictionaries Requirements: Input b returns to the upper level, input q exits the whole program   Thought: The first level of the three-level menu is province, the second level is city, and the ...

Posted by joon on Tue, 02 Jul 2019 00:26:08 +0200

Chapter VII Array Experiments

C Program Experiment Report Experiments: 1. Application of one-dimensional arrays 2. Application of two-dimensional arrays 3. Application of Character Array Name: Chen Fuzhou Experimental Place: 514 Classroom of Teaching Building Experimental Time: 2019.5.29 1. Experimental Purpose and Requirements 1. Master the definition of one-dim ...

Posted by c815902 on Sat, 01 Jun 2019 20:01:02 +0200