网络图片下载并压缩保存

 

        有时候,需要对网络的图片下载至本地服务器,并按一定比例缩小后显示,以下是图片按比例缩小的代码:

        ///<summary>
        /// 缩小图片
        /// </summary>
        /// <param name="strOldPic">源图文件名(包括路径)</param> 
        /// <param name="strNewPic">缩小后保存为文件名(包括路径)</param> 
        /// <param name="intWidth">缩小至宽度</param> 
        /// <param name="intHeight">缩小至高度</param> 
        private static void SmallPic(string strOldPic, string strNewPic, int intWidth, int intHeight) 
        {
            Bitmap objPic,objNewPic;
            try
            {
                objPic = new System.Drawing.Bitmap(strOldPic);
                objNewPic = new System.Drawing.Bitmap(objPic, intWidth, intHeight);
                objNewPic.Save(strNewPic);
            }
            catch (Exception ex) { throw ex; }
        }

        /// <summary>
        /// 按比例缩小图片，自动计算高度
        /// </summary>
        /// <param name="strOldPic">源图文件名(包括路径)</param> 
        /// <param name="strNewPic">缩小后保存为文件名(包括路径)</param> 
        /// <param name="intWidth">缩小至宽度</param> 
        private static void SmallPicByWidth(string strOldPic, string strNewPic, int intWidth)
        {
            Bitmap objPic, objNewPic;
            try
            {
                objPic = new System.Drawing.Bitmap(strOldPic);
                int intHeight = (int)((intWidth / (double)objPic.Width) * objPic.Height);
                objNewPic = new System.Drawing.Bitmap(objPic, intWidth, intHeight);
                objNewPic.Save(strNewPic);
            }
            catch (Exception ex) { throw ex; }
        }

        /// <summary> 
        /// 按比例缩小图片，自动计算宽度 
        /// </summary> 
        /// <param name="strOldPic">源图文件名(包括路径)</param> 
        /// <param name="strNewPic">缩小后保存为文件名(包括路径)</param> 
        /// <param name="intHeight">缩小至高度</param> 
        private static void SmallPicByHeight(string strOldPic, string strNewPic, int intHeight)
        {
            Bitmap objPic, objNewPic;
            try
            {
                objPic = new System.Drawing.Bitmap(strOldPic);
                int intWidth = (int)((intHeight / (double)objPic.Height) * objPic.Width);
                objNewPic = new System.Drawing.Bitmap(objPic, intWidth, intHeight);
                objNewPic.Save(strNewPic);
            }
            catch (Exception ex) { throw ex; }
        }