.net operation redis string string

One 、String String Overview

string Type in the redis Is the most common type , Its data form is key value ,value The maximum amount of data stored is 512M, It can store json data , Image data and so on .

Two 、 Use scenarios

1.session utilize redis do session Shared memory .

2. Self increment and self subtraction -- Do some website requests , Or the number of likes on the Forum , comments . It can be used redis To achieve , After completion, do data disk brushing , Put these statistics into our persistent database .

3、 ... and 、.NET operation

I use ServiceStack.Redis c# client , Very powerful , But the charge . Every hour the request reaches 6000 when , Will be restricted . If you want to use other Redis C# Client library , Can be in Redis Official website Other client libraries found in , among BeetleX.Redis and NewLife.Redis They were developed by the cement guy team and the stone guy team , You can try .

1、 Set up key Of value, Basic operation

 client.Set<string>("onekey", " The first string operation ");// write in String
 var val = client.Get<string>("onekey");// according to key obtain value
 Console.WriteLine(val);

2、 Set up multiple key value Key value pair

// Batch write redis key
client.SetAll(new Dictionary<string, string> { { "id", "1" }, { "name", "kgxk" } });
// Batch read multiple in memory key Result   If we get key non-existent , The program will return an empty string 
var getall = client.GetAll<string>(new string[] { "id", "name", "number" });
foreach (var item in getall)
{
  Console.WriteLine(item);
}

3、 Set up key Of value And set expiration time

client.Set<string>("name", "kgxk", TimeSpan.FromSeconds(1));
Task.Delay(1 * 1000).Wait();
// The expiration time can be a specific time 
//client.Set<string>("name", "kgxk", DateTime.Now.AddSeconds(1));
//client.Set<string>("name", "kgxk", DateTime.Now.AddMonths(15));
Console.WriteLine(client.Get<string>("name"));

4、 In the original key Of value Value is appended value

client.AppendToValue("name", "K");
client.AppendToValue("name", "G");
client.AppendToValue("name", "XK");
Console.WriteLine(client.Get<string>("name"));

5、 Get the old value and assign a new value

client.Set("name", "kgxk");
// Get current key The previous value of , Then replace the new result into 
var value = client.GetAndSetValue("name", " Miner's pit ");
Console.WriteLine(" Original value " + value);
Console.WriteLine(" The new value " + client.GetValue("name"));

6、 Self increasing , Returns the value after increment

// to key by sid The key of increases automatically 1 , Returns the result after autoincrement 
Console.WriteLine(client.Incr("sid"));
Console.WriteLine(client.Incr("sid"));
Console.WriteLine(client.Incr("sid"));
Console.WriteLine(" Default auto increment end ");
Console.WriteLine(client.GetValue("sid"));
// Every time it passes count Cumulative ,count Is the cumulative value 
client.IncrBy("sid", 2);
Console.WriteLine(client.Get<string>("sid"));
client.IncrBy("sid", 100);
Console.WriteLine(" The final result ***" + client.GetValue("sid"));

7、 Self reduction , Returns the value after subtraction

Console.WriteLine(client.Decr("sid"));
Console.WriteLine(client.Decr("sid"));
Console.WriteLine(client.Decr("sid"));
Console.WriteLine(" The final result " + client.GetValue("sid"));
// Through the introduction of count To lose weight   Previous results -count
client.DecrBy("sid", 2);
Console.WriteLine(" Final result " + client.GetValue("sid"));

8、add and set

• add You can only add , If there are already key Then it returns failure
• set If there is key Just replace , If not, write
• When using add How to operate redis When , If key exist , Will not operate again return false If the operation is successful, return to true

Console.WriteLine(client.Add("name", "kgxk"));
// use add Help you to judge when there is any, and do not operate , If not, write , It can only write new values , Do not modify 
Console.WriteLine(client.Add("name", " You're fine kgxk"));
Console.WriteLine(client.Get<string>("name"));

 // Use set To operate  redis When , If key If it does not exist, write the current value , And back to true, By being , Then the previous value is replaced   Returns the result of the operation 
Console.WriteLine(client.Set("name", "kgxk"));
Console.WriteLine(client.Set("name", " You're fine kgxk"));
Console.WriteLine(client.Get<string>("name"));