Tag:Character string

  • Basic program structure of go language: data type

    Time:2021-3-8

    Go language is a static programming language. This means that the compiler needs to know the type of each value in the program at compile time. The emergence of data type is to divide data into data with different memory sizes. When programming, you need to use big data to apply for big memory, so […]

  • Notes on regular expressions (2)

    Time:2021-3-8

    Regular expression in JS summary In JS, regular expressions are aRegExpObject withexec,testmethod. And inStringObject, also existsmatch,replace,search,splitMethods for manipulating regular expressions. statement There are two ways to declare regular expressions in JS (object literal / constructor), both of which produce oneRegExpObject. /pattern/flags new RegExp(pattern[, flags]) Regexp object example var pattern = /quick\s(brown).+?(jumps)/ig; var pattern = new […]

  • High performance SQL — data type selection and optimization

    Time:2021-3-8

    Data type selection and optimization 1. Why do we need to optimize the database type 2. Database type optimization principle 3. How to select database field type Text: 1. Why do we need to optimize the database type? In our previous database design experience, we often focus on the business fields of the database rather […]

  • The use of URL module in node

    Time:2021-3-8

    URL module is one of the core modules of nodejs, which is used to parse URL string and URL object url.parse(url_str[,boolean]) url.parse(url_str[,boolean])Used toURL stringToObject format. This method has two parameters, the first is URL string, the second is Boolean value, which can not be written, indicating whether it will also be usedqueryTurn to object url.parse(url_str) […]

  • Pad method in JavaScript string!

    Time:2021-3-8

    Author: Dmitri pavlutinTranslator: XiaozhiSource: Dmitri pavlutin Like again, form a habit this paperGitHub https://github.com/qq44924588…I’ve collected more categories of previous highly praised articles and sorted out a lot of my documents and tutorial materials. Welcome star and perfect, you can refer to the interview site review, I hope we have something together. Everyone said that there […]

  • DK7 switch’s support for string

    Time:2021-3-7

    Before JDK7, switch can only support byte, short, char, int or their corresponding encapsulation classes and enum types. After JDK7, switch supports string type. In the switch statement, the value of the expression cannot be null, otherwise NullPointerException will be thrown at runtime. Null cannot be used in the case clause, otherwise compilation errors will […]

  • SQL len() function usage

    Time:2021-3-7

    meaning: LEN Function returns the length of the value in a text field. Returns the number of characters in a character expression SQL LEN() grammar SELECT LEN(column_name) FROM table_name give an example: 1、LENReturn the same value for the same single byte and double byte string, such as Chinese character, English character, symbol. Note: lenWhen the […]

  • Notes on regular expressions (3)

    Time:2021-3-7

    String.replace Careful readers may find that we missed the last articleString.replaceThis is the way.String.replaceIt has more powerful usage and flexibility in JS, so it’s separated here and introduced separately. API String.replace(searchValue, replacement) String.replaceAt the same time, support regular expression or string replacement, and return a new string. Because our topic is regular expressions, the following […]

  • SDS of redis data structure

    Time:2021-3-6

    SDS(simple dynamic string), simple dynamic string. S and it’s called hacking string. Where hack is stored is the length of the string and the remaining space in SDS. The implementation of SDS insds.cIn the middle. C language string uses a character array of length N + 1 to represent the string of length N, and […]

  • Notes on regular expressions (4)

    Time:2021-3-6

    Create auriParser As a web development engineer, I am familiar with the following code: $kw = $_GET[‘keyword’]; // PHP String kw = request.getParameter(“keyword”); // JSP For the back-end language, we can easily get aurlParameter values in the request. However, when we need to get the URL parameters in the front-end project, JS has no corresponding […]

  • Notes on regular expressions (5)

    Time:2021-3-5

    Template In the back-end language, there will be corresponding template language support smarty, blade // php velocity, freemarker // jsp However, in the front end, if you want to use the template, you have to do it yourself. At this time, we have to ask outString.replaceThere’s no way. thinking Constructing regular expressions Define matching rules […]

  • Redis’s 8 data types are well written!

    Time:2021-3-5

    NoSQL development will be used more or less, but also the interview must ask knowledge. I have been asked about every interview in recent days. But I feel that the answer is not good, and there are still many knowledge points that need to be sorted out. You can view the following commands on the […]