如何从以下代码中获取返回值?我不想只是控制台记录它
function get_disk_space(callback){
checkDiskSpace('C:\\').then((diskSpace) => {
var free = Math.floor(diskSpace.free/1000000000)
var size = Math.floor(diskSpace.size/1000000000)
var used = size - free
percent = (size - free)
percent = percent/size*100
percent = Math.floor(percent)+'%'
return percent;
});
}
运行此命令将返回未定义,而在返回百分比之前运行控制台日志将给我正确的答案..
最佳答案
您可以简单地添加一个 then
处理程序来处理解析的值,例如:
function get_disk_space(callback) {
return checkDiskSpace('C:\\').then((diskSpace) => {
var free = Math.floor(diskSpace.free / 1000000000)
var size = Math.floor(diskSpace.size / 1000000000)
var used = size - free
percent = (size - free)
percent = percent / size * 100
percent = Math.floor(percent) + '%'
return percent;
});
}
为了访问 get_disk_space 函数范围之外的结果,您需要执行以下操作:
get_disk_space().then((result) => {
//log and handle your result
console.log(result);
// handle your result
});
如果您调用 get_disk_space
的函数是异步的,您可以简单地执行以下操作:
async function testFunc() {
const result = await get_disk_space();
// handle result
}
关于javascript - 从异步表达式中获取返回值,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/55550197/