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

##   
### The `HasPrefix()` method
The `strings` package provides the `HasPrefix()` method, which can be used to check if a string is a prefix of another string. 

This is used to quickly test if one or more characters match at the start of a string, without using a loop.

### Syntax
```
func HasPrefix(s, prefix string) bool
```

### Argument
- This method takes the string ```s``` and another string ```prefix``` as input. The ```HasPrefix()``` method checks if ```prefix``` is a prefix of the input string ```s```.

### Return value
- It returns ```true``` if ```s``` begins with ```prefix```, otherwise it returns `false`.

### Important points
- ```HasPrefix()``` is present in the ```strings``` standard package.
- It performs case-sensitive comparison.
- It returns ```true``` if we pass an empty string as a prefix since an empty string is the prefix of all strings.


### Code
In the code below, we imported the ```fmt``` and ```strings``` package to our program.



package main

import (
	"fmt"
	"strings"
)

func main() {
	sourceString := "Educative"
	fmt.Println(strings.HasPrefix(sourceString, "Ed"))
	fmt.Println(strings.HasPrefix(sourceString, "ed"))
	fmt.Println(strings.HasPrefix(sourceString, "ducative"))
	fmt.Println(strings.HasPrefix(sourceString, ""))
}

### Explanation
- We call the ```HasPrefix()``` method with ```"Educative"``` as the source string and ```"Ed"``` as the prefix to check. This returns ```true``` as ```"Ed"``` is the prefix of ```"Educative"```.

- We again call the ```HasPrefix()``` method with ```"Educative"``` as the source string and ```"ed"``` as the prefix to check. This returns ```false``` as ```"ed"``` is NOT the prefix of ```"Educative"``` because the ```HasPrefix()``` method is case sensitive.

- Then we call to ```HasPrefix()``` with ```"Educative"``` as the source string and ```"ducative"``` as the prefix which returns ```false```. 

- At last, we pass ```"Educative"``` as the source and an empty string as the prefix string and it returns ```true```.

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

### Output
The program prints the output below and exits:
```
true
false
false
true
```





How to check if a string begins with a prefix in Go

The HasPrefix() method

Syntax

Argument

Return value

Important points

Code

Explanation

Output

The `HasPrefix()` method