如何用零填充数字？

Question

Let's say I want to pad out a number in Go:

4 => "004"
23 => "023"

How can I do it?

Answer 1

Use the "%0xd" flag to fmt.Printf from the fmt package, where x is the number of leading zeros to pad.

import "fmt"
fmt.Printf("%03d", 4)    // will print "004"

The interface is the same as in C.