golang还能调用Windows API非常有意思，下面写了一个golang换壁纸的demo。 准备了两张bmp格式的图片，没三秒钟换一下壁纸。
主要是先通过dll获取里面api，要注意api参数的写法，dll用完了要释放句柄，这里我用缓存把api缓存起来不必每次调用都去dll里加载。
代码：
package main
import (
"log"
"syscall"
"time"
"unsafe"
)
var ApiList = map[string][]string {
"user32.dll": []string {
"MessageBoxW",
"SystemParametersInfoW",
},
"kernel32.dll": []string {
},
}
var ProcCache map[string]*syscall.Proc
func init() {
ProcCache = make(map[string]*syscall.Proc)
for dllName, apiList := range ApiList {
d, err := syscall.LoadDLL(dllName)
if err != nil {
panic(err)
}
for _, name := range apiList {
api, err := d.FindProc(name)
if err != nil {
syscall.FreeLibrary(d.Handle)
panic(err)
}
ProcCache[name] = api
}
syscall.FreeLibrary(d.Handle)
}
}
func WinCall(name string, a ...uintptr) {
if api, ok := ProcCache[name]; ok {
_, _, err := api.Call(a...)
if err != nil {
log.Println(err)
}
} else {
log.Println("api not found, name:", name)
}
}
func IntPtr(n int) uintptr {
return uintptr(n)
}
func StrPtr(s string) uintptr {
p, _ := syscall.UTF16PtrFromString(s)
return uintptr(unsafe.Pointer(p))
}
func ShowMessage(title, text string) {
WinCall("MessageBoxW", IntPtr(0), StrPtr(text), StrPtr(title), IntPtr(0))
}
func SetWallpaper(bmpPath string) {
WinCall("SystemParametersInfoW", IntPtr(20), IntPtr(0), StrPtr(bmpPath), IntPtr(3))
}
func main() {
for i := 0; i < 10; i++ {
SetWallpaper("E:\\CppProject\\WindowsProject1\\test.bmp")
time.Sleep(3 * time.Second)
SetWallpaper("E:\\CppProject\\WindowsProject1\\test2.bmp")
time.Sleep(3 * time.Second)
}
}