我想在foreach完成后执行回调，但它无法正常工作。我该怎么做？
var response = [];
myArray.forEach(function(data) {
data.asyncFunction(function(result) {
response.push(result);
});
}, function() {
console.log(response); // Not being called.
});
console.log(response); // (Empty) Executed before foreach finish.
答案 0 :(得分：8)
因为 v
SELECT T.UserID FROM dbo.VacBal as I join dbo.User as T
on I.userid = T.userid
WHERE VacationBalance > 200 and active = 1
只接受一个/* Reference imports */
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
/* method */
public byte[] getImage(byte[] bytes) throws IOException {
int width = 640;
int height = 480;
int[] shifted = new int[width * height];
// (byte) bgra to rgb (int)
for (int i = 0, j = 0; i < bytes.length; i = i + 4, j++) {
int b, g, r;
b = bytes[i] & 0xFF;
g = bytes[i + 1] & 0xFF;
r = bytes[i + 2] & 0xFF;
shifted[j] = (r << 16) | (g << 8) | b;
}
BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
bufferedImage.getRaster().setDataElements(0, 0, width, height, shifted);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ImageIO.write(bufferedImage, "JPG", baos);
byte[] ret = baos.toByteArray();
return ret;
}
。由于您在forEach内调用异步方法，因此需要检查是否所有asyn调用都已完成
callback答案 1 :(得分：3)
试试这个：
myArray.forEach(function(element, index, array){
asynchronous(function(data){
if (index === myArray.length - 1) {
response.push(data);
functionAfterForEach();
}
})
});