Add files via upload

App.config

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+    <startup> 
+
+    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/></startup>
+</configuration>

MainForm.cs

@@ -0,0 +1,158 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Windows.Forms;
+using System.IO;
+
+namespace vtt_to_srt
+{
+    public partial class MainForm : Form
+    {
+
+        public MainForm()
+        {
+            InitializeComponent();
+        }
+
+        private void AddButton_Click(object sender, EventArgs e)
+        {
+            OpenFileDialog openFileDialog = new OpenFileDialog
+            {
+                Filter = "WebVTT files (*.vtt)|*.vtt",
+                RestoreDirectory = true,
+                Multiselect = true
+            };
+
+            if (openFileDialog.ShowDialog() == DialogResult.OK)
+            {
+                foreach(string str in openFileDialog.FileNames)
+                    if(!filesListBox.Items.Contains(str))
+                        filesListBox.Items.Add(str);
+            }
+        }
+
+        private void DeleteSelectedButton_Click(object sender, EventArgs e)
+        {
+            List<int> list = new List<int>();
+            foreach (int index in filesListBox.SelectedIndices)
+                list.Add(index);
+            list.Reverse();
+            foreach (int index in list)
+                filesListBox.Items.RemoveAt(index);
+        }
+
+        private void DeleteAllButton_Click(object sender, EventArgs e)
+        {
+            filesListBox.Items.Clear();
+        }
+
+        private void BrowseButton_Click(object sender, EventArgs e)
+        {
+            using (FolderBrowserDialog fbd = new FolderBrowserDialog())
+            {
+                if (fbd.ShowDialog() == DialogResult.OK && !String.IsNullOrWhiteSpace(fbd.SelectedPath))
+                {
+                    outputFolderTextBox.Text = fbd.SelectedPath;
+                }
+            }
+        }
+
+        private void ConvertButton_Click(object sender, EventArgs e)
+        {
+            if (Directory.Exists(outputFolderTextBox.Text))
+            {
+                SwitchUIControlsEnabled();
+                foreach (string str in filesListBox.Items)
+                    ConvertToSrt(str);
+                MessageBox.Show("All files converted successfully.", "Done", MessageBoxButtons.OK, MessageBoxIcon.Information);
+                SwitchUIControlsEnabled();
+            }
+            else
+                MessageBox.Show("Output folder doesn't exist.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+
+        }
+
+        void SwitchUIControlsEnabled()
+        {
+            outputFolderTextBox.Enabled = !outputFolderTextBox.Enabled;
+            filesListBox.Enabled = !filesListBox.Enabled;
+            addButton.Enabled = !addButton.Enabled;
+            deleteSelectedButton.Enabled = !deleteSelectedButton.Enabled;
+            deleteAllButton.Enabled = !deleteAllButton.Enabled;
+            browseButton.Enabled = !browseButton.Enabled;
+            convertButton.Enabled = !convertButton.Enabled;
+        }
+
+        void ConvertToSrt(string filePath)
+        {
+            try
+            {
+                using (StreamReader stream = new StreamReader(filePath))
+                {
+                    StringBuilder output = new StringBuilder();
+                    int lineNumber = 1;
+                    while (!stream.EndOfStream)
+                    {
+                        string line = stream.ReadLine();
+                        if (IsTimecode(line))
+                        {
+                            output.AppendLine(lineNumber.ToString());
+                            lineNumber++;
+                            line = line.Replace('.', ',');
+                            line = DeleteCueSettings(line);
+                            output.AppendLine(line);
+                            bool foundCaption = false;
+                            while(true)
+                            {
+                                if (stream.EndOfStream)
+                                {
+                                    if (foundCaption)
+                                        break;
+                                    else
+                                        throw new Exception("Corrupted file: Found timecode without caption");
+                                }
+                                line = stream.ReadLine();
+                                if (String.IsNullOrEmpty(line) || String.IsNullOrWhiteSpace(line))
+                                {
+                                    output.AppendLine();
+                                    break;
+                                }
+                                foundCaption = true;
+                                output.AppendLine(line);
+                            }
+                        }
+                    }
+                    string fileName = Path.GetFileNameWithoutExtension(filePath) + ".srt";
+                    using (StreamWriter outputFile = new StreamWriter(outputFolderTextBox.Text + '\\' + fileName))
+                        outputFile.Write(output);
+                }
+            }
+            catch (Exception e)
+            {
+                MessageBox.Show(this, e.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
+            }
+        }
+
+        bool IsTimecode(string line)
+        {
+            return line.Contains("-->");
+        }
+
+        string DeleteCueSettings(string line)
+        {
+            StringBuilder output = new StringBuilder();
+            foreach (char ch in line)
+            {
+                char chLower = Char.ToLower(ch);
+                if (chLower >= 'a' && chLower <= 'z')
+                {
+                    break;
+                }
+                output.Append(ch);
+            }
+            return output.ToString();
+        }
+
+    }
+
+}