十进制度批量转换度分秒

写在代码之前：

有一条小河，因为怕湿了脚，所以去搭桥。

结果是脚没有湿，却弄脏了全身。

谷歌地图下载器下载的图片四个角点的经纬度坐标为十进制的度，在ArcGIS里做配准，由于图比较大，导出的时候做了分割，

分割成了很多张图片。需要找出其中一张与研究区一致的影像，一个个配准需要输入经纬度，但ArcGIS中输入的是度分秒，

所以，写程序对txt文件进行批量处理。代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;

namespace 十进制度转度分秒
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        string folderpath = "";
        private void button1_Click(object sender, EventArgs e)
        {
            FolderBrowserDialog fbd = new FolderBrowserDialog();
            fbd.Description = "选择包含谷歌地图下载器经纬度的文件夹";

            if (fbd.ShowDialog() == DialogResult.OK)
            {
                folderpath = fbd.SelectedPath;
            }
            textBox1.Text = folderpath;
        }

        private void button2_Click(object sender, EventArgs e)
        {
            char[] split = new char[] { ':', ',' }; //分割字符串
            folderpath = textBox1.Text;
            //获取所选文件夹路径下的所有txt文档
            List<string> list = new List<string>();
            string[] strlist = Directory.GetFiles(folderpath);
            for (int i = 0; i < strlist.Length; i++)
            {
                FileInfo f = new FileInfo(strlist[i]);
                if (f.Extension == ".txt")
                    list.Add(strlist[i]);
            }

            for (int i = 0; i < list.Count; i++)
            {
                try
                {
                    StringBuilder sb = new StringBuilder();
                    StreamReader sr = new StreamReader(list[i],Encoding.GetEncoding(936),true);
                    string s;
                    while (!sr.EndOfStream)
                    {
                        s = sr.ReadLine();
                        string[] tempstr = s.Split(split);
                        if (!tempstr[0].Contains("角"))
                        {
                            MessageBox.Show("所选择的不是谷歌地图下载器的坐标文件");
                            return;
                        }
                        else
                        {
                            //转换并写入文件
                            
                            double[] dt1 = trandu2m(tempstr[1]);
                            double[] dt2 = trandu2m(tempstr[2]);
                            string s1 = tempstr[0]+dt1[0].ToString()
                                + "°" + dt1[1].ToString()+"′"+dt1[2].ToString()+"″";
                            string s2 = dt2[0].ToString()
                                + "°" + dt2[1].ToString() + "′" + dt2[2].ToString() + "″";
                            sb.AppendLine(s1 + "，" + s2);
                        }
                    }

                    sr.Close();
                    FileStream fs = new FileStream(list[i], FileMode.Append);
                    StreamWriter sw = new StreamWriter(fs,Encoding.GetEncoding(936));
                    sw.WriteLine(); //写入一空行
                    sw.WriteLine(sb);
                    
                    sw.Close();
                }
                catch (System.Exception ex)
                {
                    throw new Exception(ex.Message);
                }  
            }

            MessageBox.Show("操作成功");
        }
        
        /// <summary>
        /// 十进制度转化为度分秒
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        private double[] trandu2m(string str)
        {
            try
            {
                //double dd = Convert.ToDouble(str);
                double[] dt = new double[3];
                dt[0] = Convert.ToDouble(str.ToString().Substring(0, str.IndexOf(".")));
                string str1= str.Substring(str.IndexOf(".")+1);
                str1 = "0." + str1;
                string str2 = (Convert.ToDouble(str1) * 60).ToString();
                dt[1] = Convert.ToDouble(str2.Substring(0,str2.IndexOf(".")));
                string str3 = str2.Substring(str2.IndexOf(".") + 1);
                str3 = "0." + str3;
                string str4 = (Convert.ToDouble(str3) * 60).ToString();
                dt[2] = Convert.ToDouble(str4);

                return dt;
            }
            catch (System.Exception ex)
            {
                throw new Exception(ex.Message);
            }
            
        }
    }
}