回答編集履歴

  Zuishinさんの手順にそってざっと作ってみました。

  大体のところはデザイナでできます。書いた部分はForm1.csとToDoItem.csです。

 

 

  using System;

 

  namespace Questions245208

  {

  public class ToDoItem

  {

  public bool Completed { get; set; }

  public DateTime Deadline { get; set; }

  public string Task { get; set; }

  }

  }

  ```

 

  using System;

  using System.Collections.Generic;

  using System.IO;

  using System.Runtime.Serialization;

  using System.Windows.Forms;

  using System.Xml;

 

  namespace Questions245208

  {

  public partial class Form1 : Form

  {

  public Form1()

  InitializeComponent();

 

  if(File.Exists("todo.xml"))

  using(var fs = new FileStream("todo.xml", FileMode.Open))

  {

  var serializer = new DataContractSerializer(typeof(List<ToDoItem>));

  toDoItemBindingSource.DataSource = serializer.ReadObject(fs);

  }

 

  private void Add_Click(object sender, EventArgs e)

  var item = new ToDoItem

  Task = textBox1.Text,

  Deadline = dateTimePicker1.Value,

  };

  toDoItemBindingSource.Add(item);

 

  private void Delete_Click(object sender, EventArgs e)

  //toDoBindingSource.RemoveCurrent();

 

  foreach(DataGridViewRow row in dataGridView1.SelectedRows)

  if(!row.IsNewRow)

  {

  dataGridView1.Rows.Remove(row);

  }

 

  private void Save_Click(object sender, EventArgs e)

  using(var xw = XmlWriter.Create("todo.xml", new XmlWriterSettings { Indent = true, }))

  var serializer = new DataContractSerializer(typeof(List<ToDoItem>));

  serializer.WriteObject(xw, toDoItemBindingSource.List);

  }

  }

  ```

 

  namespace Questions245208

  {

  partial class Form1

  {

  /// <summary>

  /// 必要なデザイナー変数です。

  /// </summary>

  private System.ComponentModel.IContainer components = null;

 

  /// <summary>

  /// 使用中のリソースをすべてクリーンアップします。

  /// </summary>

  /// <param name="disposing">マネージド リソースを破棄する場合は true を指定し、その他の場合は false を指定します。</param>

  protected override void Dispose(bool disposing)

  if(disposing && (components != null))

  components.Dispose();

  base.Dispose(disposing);

 

  #region Windows フォーム デザイナーで生成されたコード

 

  /// <summary>

  /// デザイナー サポートに必要なメソッドです。このメソッドの内容を

  /// コード エディターで変更しないでください。

  /// </summary>

  private void InitializeComponent()

  this.components = new System.ComponentModel.Container();

  this.dataGridView1 = new System.Windows.Forms.DataGridView();

  this.Add = new System.Windows.Forms.Button();

  this.Delete = new System.Windows.Forms.Button();

  this.Save = new System.Windows.Forms.Button();

  this.dateTimePicker1 = new System.Windows.Forms.DateTimePicker();

  this.textBox1 = new System.Windows.Forms.TextBox();

  this.completedColumn = new System.Windows.Forms.DataGridViewCheckBoxColumn();

  this.deadlineColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();

  this.taskColumn = new System.Windows.Forms.DataGridViewTextBoxColumn();

  this.toDoItemBindingSource = new System.Windows.Forms.BindingSource(this.components);

  ((System.ComponentModel.ISupportInitialize)(this.dataGridView1)).BeginInit();

  ((System.ComponentModel.ISupportInitialize)(this.toDoItemBindingSource)).BeginInit();

  this.SuspendLayout();

  // dataGridView1

  this.dataGridView1.AutoGenerateColumns = false;

  this.dataGridView1.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize;

  this.dataGridView1.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {

  this.completedColumn,

  this.deadlineColumn,

  this.taskColumn});

  this.dataGridView1.DataSource = this.toDoItemBindingSource;

  this.dataGridView1.Location = new System.Drawing.Point(12, 34);

  this.dataGridView1.Name = "dataGridView1";

  this.dataGridView1.RowTemplate.Height = 21;

  this.dataGridView1.SelectionMode = System.Windows.Forms.DataGridViewSelectionMode.FullRowSelect;

  this.dataGridView1.Size = new System.Drawing.Size(604, 404);

  this.dataGridView1.TabIndex = 0;

  // Add

  this.Add.Location = new System.Drawing.Point(622, 352);

  this.Add.Name = "Add";

  this.Add.Size = new System.Drawing.Size(80, 40);

  this.Add.TabIndex = 1;

  this.Add.Text = "登録";

  this.Add.UseVisualStyleBackColor = true;

  this.Add.Click += new System.EventHandler(this.Add_Click);

  // Delete

  this.Delete.Location = new System.Drawing.Point(708, 352);

  this.Delete.Name = "Delete";

  this.Delete.Size = new System.Drawing.Size(80, 40);

  this.Delete.TabIndex = 2;

  this.Delete.Text = "削除";

  this.Delete.UseVisualStyleBackColor = true;

  this.Delete.Click += new System.EventHandler(this.Delete_Click);

  // Save

  this.Save.Location = new System.Drawing.Point(622, 398);

  this.Save.Name = "Save";

  this.Save.Size = new System.Drawing.Size(166, 40);

  this.Save.TabIndex = 3;

  this.Save.Text = "保存";

  this.Save.UseVisualStyleBackColor = true;

  this.Save.Click += new System.EventHandler(this.Save_Click);

  // dateTimePicker1

  this.dateTimePicker1.Location = new System.Drawing.Point(623, 62);

  this.dateTimePicker1.Name = "dateTimePicker1";

  this.dateTimePicker1.Size = new System.Drawing.Size(166, 19);

  this.dateTimePicker1.TabIndex = 4;

  // textBox1

  this.textBox1.Location = new System.Drawing.Point(624, 105);

  this.textBox1.Name = "textBox1";

  this.textBox1.Size = new System.Drawing.Size(165, 19);

  this.textBox1.TabIndex = 5;

  // completedColumn

  this.completedColumn.DataPropertyName = "Completed";

  this.completedColumn.HeaderText = "完了";

  this.completedColumn.Name = "completedColumn";

  this.completedColumn.Width = 50;

  // deadlineColumn

  this.deadlineColumn.DataPropertyName = "Deadline";

  this.deadlineColumn.HeaderText = "期限";

  this.deadlineColumn.Name = "deadlineColumn";

  // taskColumn

  this.taskColumn.DataPropertyName = "Task";

  this.taskColumn.HeaderText = "やること";

  this.taskColumn.Name = "taskColumn";

  this.taskColumn.Width = 300;

  // toDoItemBindingSource

  this.toDoItemBindingSource.DataSource = typeof(Questions245208.ToDoItem);

  // Form1

  this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);

  this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;

  this.ClientSize = new System.Drawing.Size(800, 450);

  this.Controls.Add(this.textBox1);

  this.Controls.Add(this.dateTimePicker1);

  this.Controls.Add(this.Save);

  this.Controls.Add(this.Delete);

  this.Controls.Add(this.Add);

  this.Controls.Add(this.dataGridView1);

  this.Name = "Form1";

  this.Text = "Form1";

  ((System.ComponentModel.ISupportInitialize)(this.dataGridView1)).EndInit();

  ((System.ComponentModel.ISupportInitialize)(this.toDoItemBindingSource)).EndInit();

  this.ResumeLayout(false);

  this.PerformLayout();

 

 

  #endregion

 

  private System.Windows.Forms.DataGridView dataGridView1;

  private System.Windows.Forms.Button Add;

  private System.Windows.Forms.Button Delete;

  private System.Windows.Forms.Button Save;

  private System.Windows.Forms.DateTimePicker dateTimePicker1;

  private System.Windows.Forms.TextBox textBox1;

  private System.Windows.Forms.BindingSource toDoItemBindingSource;

  private System.Windows.Forms.DataGridViewCheckBoxColumn completedColumn;

  private System.Windows.Forms.DataGridViewTextBoxColumn deadlineColumn;

  private System.Windows.Forms.DataGridViewTextBoxColumn taskColumn;

  }

  }

  ```