UIImage+Expansion.h文件

/**
 *  屏幕截图
 *
 *  @param view 需要截的view
 *
  */
+ (instancetype)captureWithView:(UIView *)view;

UIImage+Expansion.m文件

#pragma mark - 屏幕截图
+ (instancetype)captureWithView:(UIView *)view
{
    // 1.开启上下文
    UIGraphicsBeginImageContextWithOptions(view.frame.size, NO, 0);
    // 2.将控制器view的layer渲染到上下文
    [view.layer renderInContext:UIGraphicsGetCurrentContext()];
    // 3.取出图片
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    // 4.结束上下文
    UIGraphicsEndImageContext();

    return newImage;
}