The **```strings```** **package** is a Go standard library package that contains functions to manipulate UTF-8 encoded strings.

##   
### The `Contains()` method

The **```Contains()```** **method** can be used in Go to check if a substring is contained in a string.

##   
### Syntax
```
func Contains(s, substr string) bool
```

##    
### Arguments
- This method takes the string ```s``` and a substring ```substr``` as input.

##    
### Returns
- It returns `true` if the substring is present in the input string and `false` if it is not present.
- This method is case-sensitive.



##   
### Code
First, we import the ```fmt``` and ```strings``` package to our program in the code below:


package main

import (
	"fmt"
	"strings"
)

func main() {
  str1 := "educative.io"
	fmt.Println(str1, "io", strings.Contains(str1, "io"))
	fmt.Println(str1, "shot", strings.Contains(str1, "shot"))
	fmt.Println(str1, "", strings.Contains(str1, ""))
}


##    
### Explanation
- We call the ```Contains()``` method with ```"educative.io"``` as the input string and ```"io"``` as the substring to search after importing `fmt`. This returns ```true``` becuase the input substring ```"io"``` is contained in the string ```"educative.io"```.

- We call the ```Contains()``` method with ```"educative.io"``` as the input string and ```"shot"``` as the substring to search. This returns ```false``` because the input substring ```"shot"``` is not contained in the string ```"educative.io"```.

- We test the ```Contains()``` method with ```"educative.io"``` as the input string and empty string(```""```) as the substring to search. This returns ```true``` because all strings contain the empty string.

- We show the output of all these operations using the ```Println()``` method of the ```fmt``` package.

##   
### Output
The program prints the output below and exits:
```
educative.io io true
educative.io shot false
educative.io  true
```

How to check if a substring is contained in a string in Go

The Contains() method

Syntax

Arguments

Returns

Code

Explanation

Output

The `Contains()` method