GetImage，華蓋

GetImage，華蓋

check路徑是是否有效，網絡訪問地址。notfound查找不到，httpstatuscode枚舉數較多，根據自己想要的設置就好了。

public bool checkValid(string path)
        {
            HttpWebRequest request = HttpWebRequest.Create(path) as HttpWebRequest;
            request.Method = "GET";
            request.ProtocolVersion = new Version(1, 1);
            HttpWebResponse response = request.GetResponse() as HttpWebResponse;
            if (response.StatusCode==HttpStatusCode.NotFound)
            {
                return false;
            }
            return true;
        }

根據網絡地址還是本地路徑，進行獲取圖片數據，保存到本地文件下。注意數據流的權限FileAccess.ReadWrite

保存有可能出錯，在外層套了個try catch，不過各個節進行判斷更好，能夠拿到出錯點。

if (url.IndexOf("http://") == 0 || url.IndexOf("https://") == 0)
                {
                    WebRequest request = (WebRequest)HttpWebRequest.Create(url);
                    WebResponse response = request.GetResponse();
                    Stream stream = response.GetResponseStream();
                    FileStream fileStream = File.Create(filePath);
                    byte[] buffer = new byte[(int)response.ContentLength];
                    int numReadByte = 0;
                    while ((numReadByte = stream.Read(buffer, 0, (int)response.ContentLength)) != 0)
                    {
                        fileStream.Write(buffer, 0, numReadByte);
                    }
                    fileStream.Close();
                    stream.Close();
                }
                else
                {
                    FileStream fs = File.Open(url, FileMode.Open, FileAccess.ReadWrite, FileShare.Read);
                    FileStream fileStream = File.Create(filePath);
                    Byte[] image = new Byte[(int)fs.Length];
                    int numReadByte = 0;
                    while ((numReadByte = fs.Read(image, 0, (int)fs.Length)) != 0)
                    {
                        fileStream.Write(image, 0, numReadByte);
                    }
                    fs.Close();
                    fileStream.Close();
                }