String_Tutorial

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Text.RegularExpressions; //Add to work with Regex

namespace Zau_String_Class_Lab_Assignment
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        //Finding 2nd white space position
        private void btnIndexOfSecondSpace_Click(object sender, EventArgs e)
        {
            richTextBox1.Clear();

            string inputstr = txtInputStr.Text;
            //get index of first whitespace
            char whitespace = ' ';
            int index1 = inputstr.IndexOf(whitespace);
            //get index of second whitespace
            int index2 = inputstr.IndexOf(whitespace, index1 + 1);
            richTextBox1.Text =
                "Index of second whitespace is: " + index2;
         
            //===================Different way to do==============
            //string inputStr = txtInputStr.Text;
            //string regex = @"(\s)";
            //Match match = Regex.Match(inputStr, regex);
            //if (match.Success)
            //{
            //    match = match.NextMatch();
            //    richTextBox1.Text = "Index of 2nd position is: " + match.Index;
            //}
            //else
            //{
            //    richTextBox1.Text = "No 2nd white space position was found.";
            //}        
        }

        //Count words in string
        private void btnCountWordInString_Click(object sender, EventArgs e)
        {
            richTextBox1.Clear();
            string inputStr = txtInputStr.Text;
            char[] seperator = {' '};
            string[] words = inputStr.Split(seperator, StringSplitOptions.RemoveEmptyEntries);
            richTextBox1.Text = "This string contains " + words.Length.ToString() + " words";
        }

        private void btnSwapFirstAndLastWord_Click(object sender, EventArgs e)
        {
            richTextBox1.Clear();
            if (txtInputStr.Text != String.Empty)
            {
                string inputStr = txtInputStr.Text;
                char[] seperator = {' '};
                string[] words = inputStr.Split(seperator, StringSplitOptions.RemoveEmptyEntries);
                string tempWord = words[0];
                words[0] = words[words.Length - 1];
                words[words.Length - 1] = tempWord;
                foreach (string word in words)
                {
                    richTextBox1.AppendText(word + " ");
                }
            }
        }

        private void btnInsertWordIn2ndLast_Click(object sender, EventArgs e)
        {
            ///Insert new word before the last word in the input string
            string inputstr = txtInputStr.Text;
            if (inputstr != String.Empty)
            {
                //get index of first whitespace
                char whitespace = ' ';
                //get word to insert
                string word = txtSubstr.Text;
                //=========================use the insert method in the String class=====
                //get index of the last whitespace
                int index = inputstr.LastIndexOf(whitespace);
                if (index > 0)
                {
                    inputstr = inputstr.Insert(index + 1, word + " ");
                }
                else
                {
                    //the inputstr has one word only, insert at index:0
                    inputstr = inputstr.Insert(0, word + " ");
                }
                txtInputStr.Text = inputstr;
            }
            //=================different way to do=============================

            //if (txtInputStr.Text != String.Empty && txtSubstr.Text != String.Empty)
            //{
            //    string inputStr = txtInputStr.Text.Trim();
            //    string additionalString = txtSubstr.Text.Trim();
            //    char[] seperator = {' '};
            //    List<string> wordsList = inputStr.Split(seperator, StringSplitOptions.RemoveEmptyEntries).ToList<string>();
            //    wordsList.Insert(wordsList.Count - 1, additionalString);

            //    for (int i = 0; i < wordsList.Count; i++)
            //    {
            //        richTextBox1.AppendText(wordsList[i] + " ");
            //    }
            //}
            //else
            //{
            //    MessageBox.Show("Both The Input TextBox And The Text To Insert TextBox Must Be Populated.");
            //}
            //txtSubstr.Clear();
        }

        private void btnSearch_Click(object sender, EventArgs e)
        {
            if (txtSearchName.Text.Length == 1)
            {
                char inputChar = Convert.ToChar(txtSearchName.Text);
                string[] names = { "Alex", "Anna", "Bawk", "Benforster", "Charle", "Dan", "Deck", "Zau" };
                foreach (string name in names)
                {
                    if (name[0] == inputChar)
                        richTextBox1.AppendText(name + "\n");
                }
            }
        }

        private void btnEnterString_Click(object sender, EventArgs e)
        {
            string inputstr = txtInputStr.Text;
            richTextBox1.AppendText (inputstr);
            txtInputStr.Clear();
        }

        //Text replace
        private void btnWordToChange_Click(object sender, EventArgs e)
        {
            string strLine = richTextBox1.Text;
            if (strLine != string.Empty)
            {
                string Word2Change = txtWordToChange.Text;
                string newWord = txtNewWord.Text;
                string correctString = strLine.Replace(Word2Change, newWord);

                richTextBox1.AppendText("\n" + correctString);
            }
        }
    }
}
//=====================LAB ASSINGMENT FOR TUESDAY 6/17===============
//Create a new project where user can enter main string
//Determine the index of the second whitespace
//Determine the number of words in the main string
//Swap the first and last words
//Insert a new word (or substring) right before the last word of the main string.
//Create an array of string. Populate it with names
//Use a foreach that displays only the names that start 
//with a some character. (This character is read from user).

/// =====================6/18/2014====================
/// provide a way to replace any word by a new word
/// Ask user which word to replace
/// Get the new word
/// replace it
/// Display outcome