截取屏幕的一块区域并且声称图片

在游戏开发过程中，我们经常遇到让我们分享截图的功能，这个时候首先要接入对应分享平台的SDK，然后在把截取的区域按照SDK相应的格式发送过去，达到相应的目的，接下来直接上代码，

// Call after WaitForEndOfFrame.
    private IEnumerator ShareToSocialNetworkShareOnly_Internal(RectTransform shareArea)
    {
        yield return new WaitForEndOfFrame();

        var reqInfo = new MSDKFriendReqInfo();
        reqInfo.Type = (int)FriendReqType.Friend_REQ_IMG;
        reqInfo.ImagePath = ProcessShareTexture(shareArea);
        //reqInfo.ThumbPath = appSmallIconPath;
        MSDKFriend.Share(reqInfo);
    }


private string ProcessShareTexture(RectTransform shareArea)
    {
        // Delete old image path.
        string shareImgPath = Path.Combine(Application.temporaryCachePath, "ShareImage.png");
        FileUtility.DeleteFileIfExist(shareImgPath);

        // Get the share screen size we need.
        Rect shareScreenRect = GetShareScreenSize(Camera.main, UIWindowManager.Instance.m_UICamera, shareArea);

        // Read screen pixels into share texture.
        Texture2D shareTexture = AcquireShareTexture((int)shareScreenRect.width, (int)shareScreenRect.height);
        shareTexture.ReadPixels(shareScreenRect, 0, 0, false);
        shareTexture.Apply();

        // Save share texture data.
        byte[] imageData = shareTexture.EncodeToPNG();
        File.WriteAllBytes(shareImgPath, imageData);
        Debug.Log("Save share image to: " + shareImgPath);

        return shareImgPath;
    }

先截图，然后把相应的截图在unity运行时保存在临时缓存区域，可以在运行游戏时预览效果