Go - 向函数传递指针


Go 编程语言允许您传递指向函数的指针。为此,只需将函数参数声明为指针类型即可。

在下面的示例中,我们将两个指针传递给函数并更改函数内部的值,该值反映在调用函数中 -

package main

import "fmt"

func main() {
   /* local variable definition */
   var a int = 100
   var b int = 200

   fmt.Printf("Before swap, value of a : %d\n", a )
   fmt.Printf("Before swap, value of b : %d\n", b )

   /* calling a function to swap the values.
   * &a indicates pointer to a ie. address of variable a and 
   * &b indicates pointer to b ie. address of variable b.
   */
   swap(&a, &b);

   fmt.Printf("After swap, value of a : %d\n", a )
   fmt.Printf("After swap, value of b : %d\n", b )
}
func swap(x *int, y *int) {
   var temp int
   temp = *x    /* save the value at address x */
   *x = *y      /* put y into x */
   *y = temp    /* put temp into y */
}

当上面的代码被编译并执行时,它会产生以下结果 -

Before swap, value of a :100
Before swap, value of b :200
After swap, value of a :200
After swap, value of b :100
go_pointers.htm