use. Net analysis Net talent challenge participation

background

C# Is my 2012 Contacted in college courses in ,.NET Framework I've been using it so far . from 2014 year .NET Open source ,2019 Released in .NET Core 3 When , The company happens to have Nvidia Jetson platform Linux Development tasks of embedded devices ,.NET It just applies to Windows, Linux, and macOS Cross platform solutions for . It's easy for me to get started , It began a new process of understanding it , According to Microsoft's official .NET The document has also done several hands-on projects .

21 At the end of the year, I helped university teachers develop a garden credit evaluation system , This task can be said to be quite urgent , All the front and rear ends are completed by one person , There are only three or four days off on New Year's Day , Although the task is arduous , It's a challenge , Just then I finished learning .NET Of 《 Create your own first Web application 》, Let the challenge be more intense —— use .NET. In fact, it's not to challenge yourself , A better way to learn a language is to follow the project while learning and writing , It's twelve o'clock in the middle of the night , Fortunately, the delivery was completed on time .

At that time, the middleware for authentication and authorization written by myself also put Jwt The authentication is realized once . ok , This is the consequence of not having a teacher . Then when I finish my project, I'm free , Just in the circle of friends, I saw what Mr. Yang Zhongke sent .NET Recording and broadcasting sharing . really , What a timely rain .

Then I received the invitation from Mr. Yang's circle of friends , I really don't covet that there is something in the prize that Mr. Yang hasn't sent yet .NET New book .

So I took part in 《.NET 20 Annual learning challenge ｜ seek .NET Technical expert 》 , And completed the challenge of three modules . Through these three challenges, we are systematically right .NET Have a preliminary understanding of the ability of . Find out .NET Can do more interesting things , adopt Xamarin Preliminary understanding of Technology , I played with the Xiaomi watch that fell gray at the table because of the epidemic , Recently, it is being studied with Xamarin How technology simulates through Bluetooth HID Equipment control computer , Be a flying rat between your wrists .

Back to the challenge , The challenge is 5 month 21 End of the day , I just want to ask the organizer about Mr. Yang's book , ah , No , It's a prize , You see, I have a chance ？

Ample food and clothing by working with our own hands. , It's over to grab and analyze the ranking list by yourself .

Knowledge needed

Based on the code I have completed , I've sorted out , Complete this small project （ Everything is a project ） The required knowledge points .

First, we need to get the data of the leaderboard , You may need to use reptile Technology , Capture and analyze web pages , Then when analyzing the web page request , I found that the official ranking data is through API Acquired , And no authentication is required , This is too convenient . We can pull the ranking data at one time by slightly changing the parameters .

https://docs.microsoft.com/api/challenges/17c618cc-3c82-4a29-b2c6-d78b1de10b98/leaderboard?%24top=100&%24skip=0

F12 Open web debugging , Get the corresponding challenge ranking page as above API Address , The parameter top Change it to 100,skip Change it to 0 that will do .

In this way, other technologies or knowledge points we need are as follows ：

• adopt HttpClient Use REST service
• Asynchronous programming async await Basic use
• Use System.Text.Json analysis Json data
• LINQ Basic approach

Of course, there are other unnecessary , Such as anonymous objects .

Realize the idea

Prepare the data

First, create an anonymous object based on the ranking data of the three challenges

// API  There is a course name in the , Write it directly in order to recognize 
var apiInfo = new[]{
    
    (
        title:"C#  Study ",
        url:"https://docs.microsoft.com/api/challenges/17c618cc-3c82-4a29-b2c6-d78b1de10b98/leaderboard?%24top=100&%24skip=0"
    ),
    (
        title:"ASP.NET Core  Development ",
        url:"https://docs.microsoft.com/api/challenges/b64cc891-e999-4652-909b-d545698a2e60/leaderboard?%24top=100&%24skip=0"
    ),
    (
        title:".NET  Mobile application ",
        url:"https://docs.microsoft.com/api/challenges/38ec3c07-3ce6-4fb8-b423-b79166202364/leaderboard?%24top=100&%24skip=0"
    )
};

Design objects that store data

Create a class that stores the challenger's learning information , It contains the name of the Challenger userName , Number of challenges completed learnNum And the challenges accomplished learnName , And a method to add a new challenge class addClass

public class StudyInfo {
    
    public StudyInfo(string userName, int learnNum, List<string> learnName)
    {
    
        this.userName = userName;
        this.learnNum = learnNum;
        this.learnName = learnName;
    }
    public string userName {
     get;private set; }
    public int learnNum {
     get; private set; }
    public List<string> learnName{
     get; private set; }
    public void addClass(string className) {
    
        this.learnNum++;
        this.learnName.Add(className);
    }
}

Leaderboard data acquisition

Use HttpClient Get the data of challenge leaderboard

var client = new HttpClient();
foreach (var item in apiInfo)
{
    
    string jsoninfo = await client.GetStringAsync(item.url);
    //  analysis 
}

Data analysis and output

Conduct json Data analysis , Through the specific returned content, we can easily find the meaning represented by the field .

totalScoreUnits Indicates the number of sections of this challenge , Only by completing so many sections of learning can we complete the challenge , Use var user = new List<StudyInfo>(); To store user challenge information , Create or update data according to the analysis results . Finally, the results are arranged in reverse order and output to the file .

stay System.Text.Json We need to pay attention to several points in the use of ：

• Acquired json The value of , We need to force data conversion , Save the user's learning course score Need to use float type
• Traverse json Array time , You need to put it first JsonNode Object to carry out AsArray() Handle ,JsonNode It is not supported foreach Of
• The final output json Serialization , Need to carry out options Set up , In this way, Chinese characters will not be encoded

var options = new JsonSerializerOptions {
     Encoder = JavaScriptEncoder.Create(UnicodeRanges.All) };

JsonNode jsonNode = JsonNode.Parse(jsoninfo)!;
//  Total number of courses 
int classnum = (int)jsonNode["totalScoreUnits"]!;
foreach (var uinfo in jsonNode["results"]!.AsArray())
{
    
    //  Users who have finished learning 
    if ((float)uinfo["score"]! == classnum)
    {
    
        //  See if there is any information about this user 
        var temp = user.FirstOrDefault(e => e.userName == (string)uinfo["userDisplayName"]!);
        if (temp is null)
        {
    
            //  Initially create this user 
            user.Add(new StudyInfo((string)uinfo["userDisplayName"]!, 1, new List<string>() {
     item.title }));
        }
        else
        {
    
            //  Yes , Update learning data 
            temp.addClass(item.title);
        }
    }
}
//  Reverse order and turn to json The characters are stored in the file 
var jsonRes = JsonSerializer.Serialize(user.OrderByDescending(x => x.learnNum), options);
File.WriteAllText("output.json", jsonRes);

Make a simple analysis

It's mostly used here Linq operation , If the Linq Don't understand , You can take a look at Mr. Yang's related courses .

//  A brief analysis of 
Console.WriteLine($" complete 《C#  Study 》{
      user.Where(x=>x.learnName.IndexOf("C#  Study ")>-1).Count()} people ");
Console.WriteLine($" complete 《ASP.NET Core  Development 》{
      user.Where(x => x.learnName.IndexOf("ASP.NET Core  Development ") > -1).Count()} people ");
Console.WriteLine($" complete 《.NET  Mobile application 》{
      user.Where(x => x.learnName.IndexOf(".NET  Mobile application ") > -1).Count()} people ");
Console.WriteLine($" Only complete  1  Challenge  {
      user.Where(x => x.learnNum == 1).Count()} people ");
Console.WriteLine($" Only complete  2  Challenge  {
      user.Where(x => x.learnNum ==2).Count()} people ");
Console.WriteLine($" To complete  3  Challenge  {
      user.Where(x => x.learnNum == 3).Count()} people \n  Namely ");

foreach (var item in user.Where(x => x.learnNum == 3)) {
    
    Console.WriteLine(item.userName);
}

Last

The detailed code implementation I put in .Net Analysis of talent challenge participation github , Students who are interested in it can choose .

.NET Is a free cross platform open source Developer Platform , hope .NET Can develop better and better . If you want to know more about .NET , It is highly recommended to go to B Stand and pay attention to Mr. Yang Zhongke To learn his related video courses . You can also focus on “dotNet Cross platform ” Official account to learn more .NET technology ;.NET Learning and community activities Can pay attention to ：MSReactor .