如何在Go中创建一个包含单个项的数组？

Let's say a function takes an array of strings:

func Join(strs []string) {
     ...
}

I have a single string:

a := "y'all ain't got the honey nut?"

How can I convert that string into an array?

You can create a slice of one item using the following convention:

a := "y'all ain't got the honey nut?"
singleItemArray := []string{a}

strings.Join(singleItemArray);

The question as phrased actually references Arrays and Slices. The question text is about an array and the code is illustrating using a slice. Therefore there two questions are implied; pass a single item slice, and pass a single item array.

An array: var a [1]string A slice: var s []string

Passing a single item slice to the function:

func SliceFunc( slc []string) {
    fmt.Println(slc)
}

func main() {
    a := "stringy"
    SliceFunc( []string{a} )
    // or an actual array to the same function
    b := [...]string { "thingy" }
    SliceFunc( []string{b[0] )  
}

Passing a single item array to the function.

Here there is an issue, as an array has a fixed length and as a parameter to a function it cannot accept different length arrays so we are left with working function which has limited flexibility:

func ArrayFunc( arr [1]string) {
    fmt.Println(slc)
}

func main() {
    var a [1]string
    a[0] = "stringy"
    ArrayFunc( a )  
}

It seems that as a generalization sticking to slices is a more flexible solution.

(If you would like more on Slices and Arrays here one blog by Andrew Gerrand covering go slices usage and internals.)

The actual answer to your question is as simple as []string{"string"}, as miltonb said.

But what I wanted to point out is how easy it is to write and use a variadic function in Go, a function with a variable number of arguments.

You can change signature of your function to F(a ...string). Then, a is slice in the function F, and you can call it like F("a") and F("a", "b"). And when you actually have a slice or array, you can pass it to F by calling F(a...).

Not sure if this syntax fits your job, but I wanted to let you know about it as an option.