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トップに関する質問電卓アプリの作成でのバグ　0.3*6=1.79になってしまう

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質問編集履歴

1

コードをインデント

2020/03/12 08:09

投稿

Gunjirk
Gunjirk

スコア23

test CHANGED
File without changes
test CHANGED
@@ -40,270 +40,274 @@
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- using System;
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-
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- using System.Collections.Generic;
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-
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- using System.ComponentModel;
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-
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- using System.Data;
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-
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- using System.Drawing;
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-
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- using System.Linq;
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-
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- using System.Text;
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-
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- using System.Threading.Tasks;
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-
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- using System.Windows.Forms;
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-
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-
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-
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- namespace WindowsFormsApp1
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-
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- {
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-
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- public partial class Form1 : Form
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-
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- {
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-
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-
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-
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- public Form1()
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-
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- {
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-
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- InitializeComponent();
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-
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- }
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-
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-
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-
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- bool isFirst = true;
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-
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- double val1 = 0;
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-
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-
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-
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- private void Form1_Load(object sender, EventArgs e)
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-
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- {
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-
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-
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-
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- }
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-
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-
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-
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- private void btnNumber_Click(object sender, EventArgs e)
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-
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- {
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-
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- if (isFirst)
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-
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- {
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-
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- txtDisplay.Text = "";
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-
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- isFirst = false;
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-
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- }
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-
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- String text = txtDisplay.Text + ((Button)sender).Text;
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-
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-
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-
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- //文字列　-> 数値
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-
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- double d = Convert.ToDouble(text);
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-
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-
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-
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- //数値 -> 文字列(先頭の0が消える)
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-
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- String text2 = d.ToString();
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-
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- txtDisplay.Text = text2;
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-
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- }
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-
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-
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-
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- enum sign { blank, ADD, SUB, MUL, DIV };
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-
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- sign exec = sign.blank;
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-
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-
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-
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- //クリア
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-
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- private void button_clear_Click(object sender, EventArgs e)
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-
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- {
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-
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- exec = sign.blank;
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-
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- txtDisplay.Text = "0";
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-
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- val1 = 0;
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-
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- isFirst = true;
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-
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- }
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-
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-
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-
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- //小数点
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-
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- private void button_dot_Click(object sender, EventArgs e)
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-
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- {
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-
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- //小数点の重複チェック
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-
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- if(txtDisplay.Text.IndexOf(".") >= 1)
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-
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- {
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-
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- //すでに小数点がある
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-
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- return;
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-
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- }
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-
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- txtDisplay.Text = txtDisplay.Text + ".";
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-
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-
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-
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- }
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-
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-
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-
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- //足し算。
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-
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- private void button_tasu_Click(object sender, EventArgs e)
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-
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- {
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-
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- if (!isFirst) calc();
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-
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- exec = sign.ADD;
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-
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- }
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-
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-
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-
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- //引き算。
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-
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- private void button_hiku_Click(object sender, EventArgs e)
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-
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- {
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-
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- if (!isFirst) calc();
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-
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- exec = sign.SUB;
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-
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- }
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-
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-
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-
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- //掛け算。
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-
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- private void button_kakuru_Click(object sender, EventArgs e)
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-
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- {
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-
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- if (!isFirst) calc();
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-
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- exec = sign.MUL;
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-
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- }
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-
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-
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-
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- //割り算。
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-
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- private void button_waru_Click(object sender, EventArgs e)
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-
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- {
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-
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- if (!isFirst) calc();
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-
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- exec = sign.DIV;
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-
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- }
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-
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-
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-
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- //イコール。
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-
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- private void button_wa_Click(object sender, EventArgs e)
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-
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- {
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-
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- calc();
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-
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- }
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-
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-
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-
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- private void calc()
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-
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- {
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-
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- double val2 = Convert.ToDouble(txtDisplay.Text);
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-
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- switch (exec)
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-
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- {
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-
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- case sign.ADD:
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-
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- val1 += val2;
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-
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- break;
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-
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- case sign.SUB:
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-
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- val1 -= val2;
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-
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- break;
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-
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- case sign.MUL:
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-
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- val1 *= val2;
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-
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- break;
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-
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- case sign.DIV:
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-
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- val1 /= val2;
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-
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- break;
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-
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- default:
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-
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- val1 = val2;
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-
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- break;
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-
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- }
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-
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-
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-
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- double result = Math.Truncate(val1 * 100.0) / 100.0;
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-
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-
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-
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- txtDisplay.Text = result.ToString();
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-
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- isFirst = true;
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-
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- }
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-
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- }
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-
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-
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-
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- }
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+
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+
45
+ > using System;
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+
47
+ > using System.Collections.Generic;
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+
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+ > using System.ComponentModel;
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+
51
+ > using System.Data;
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+
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+ > using System.Drawing;
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+
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+ > using System.Linq;
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+
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+ > using System.Text;
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+
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+ > using System.Threading.Tasks;
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+
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+ > using System.Windows.Forms;
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+
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+ >
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+
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+ > namespace WindowsFormsApp1
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+
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+ > {
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+
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+ > public partial class Form1 : Form
70
+
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+ > {
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+
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+ >
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+
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+ > public Form1()
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+
77
+ > {
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+
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+ > InitializeComponent();
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+
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+ > }
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+
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+ >
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+
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+ > bool isFirst = true;
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+
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+ > double val1 = 0;
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+
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+ >
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+
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+ > private void Form1_Load(object sender, EventArgs e)
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+
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+ > {
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+
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+ >
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+
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+ > }
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+
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+ >
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+
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+ > private void btnNumber_Click(object sender, EventArgs e)
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+
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+ > {
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+
105
+ > if (isFirst)
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+
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+ > {
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+
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+ > txtDisplay.Text = "";
110
+
111
+ > isFirst = false;
112
+
113
+ > }
114
+
115
+ > String text = txtDisplay.Text + ((Button)sender).Text;
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+
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+ >
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+
119
+ > //文字列　-> 数値
120
+
121
+ > double d = Convert.ToDouble(text);
122
+
123
+ >
124
+
125
+ > //数値 -> 文字列(先頭の0が消える)
126
+
127
+ > String text2 = d.ToString();
128
+
129
+ > txtDisplay.Text = text2;
130
+
131
+ > }
132
+
133
+ >
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+
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+ > enum sign { blank, ADD, SUB, MUL, DIV };
136
+
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+ > sign exec = sign.blank;
138
+
139
+ >
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+
141
+ > //クリア
142
+
143
+ > private void button_clear_Click(object sender, EventArgs e)
144
+
145
+ > {
146
+
147
+ > exec = sign.blank;
148
+
149
+ > txtDisplay.Text = "0";
150
+
151
+ > val1 = 0;
152
+
153
+ > isFirst = true;
154
+
155
+ > }
156
+
157
+ >
158
+
159
+ > //小数点
160
+
161
+ > private void button_dot_Click(object sender, EventArgs e)
162
+
163
+ > {
164
+
165
+ > //小数点の重複チェック
166
+
167
+ > if(txtDisplay.Text.IndexOf(".") >= 1)
168
+
169
+ > {
170
+
171
+ > //すでに小数点がある
172
+
173
+ > return;
174
+
175
+ > }
176
+
177
+ > txtDisplay.Text = txtDisplay.Text + ".";
178
+
179
+ >
180
+
181
+ > }
182
+
183
+ >
184
+
185
+ > //足し算。
186
+
187
+ > private void button_tasu_Click(object sender, EventArgs e)
188
+
189
+ > {
190
+
191
+ > if (!isFirst) calc();
192
+
193
+ > exec = sign.ADD;
194
+
195
+ > }
196
+
197
+ >
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+
199
+ > //引き算。
200
+
201
+ > private void button_hiku_Click(object sender, EventArgs e)
202
+
203
+ > {
204
+
205
+ > if (!isFirst) calc();
206
+
207
+ > exec = sign.SUB;
208
+
209
+ > }
210
+
211
+ >
212
+
213
+ > //掛け算。
214
+
215
+ > private void button_kakuru_Click(object sender, EventArgs e)
216
+
217
+ > {
218
+
219
+ > if (!isFirst) calc();
220
+
221
+ > exec = sign.MUL;
222
+
223
+ > }
224
+
225
+ >
226
+
227
+ > //割り算。
228
+
229
+ > private void button_waru_Click(object sender, EventArgs e)
230
+
231
+ > {
232
+
233
+ > if (!isFirst) calc();
234
+
235
+ > exec = sign.DIV;
236
+
237
+ > }
238
+
239
+ >
240
+
241
+ > //イコール。
242
+
243
+ > private void button_wa_Click(object sender, EventArgs e)
244
+
245
+ > {
246
+
247
+ > calc();
248
+
249
+ > }
250
+
251
+ >
252
+
253
+ > private void calc()
254
+
255
+ > {
256
+
257
+ > double val2 = Convert.ToDouble(txtDisplay.Text);
258
+
259
+ > switch (exec)
260
+
261
+ > {
262
+
263
+ > case sign.ADD:
264
+
265
+ > val1 += val2;
266
+
267
+ > break;
268
+
269
+ > case sign.SUB:
270
+
271
+ > val1 -= val2;
272
+
273
+ > break;
274
+
275
+ > case sign.MUL:
276
+
277
+ > val1 *= val2;
278
+
279
+ > break;
280
+
281
+ > case sign.DIV:
282
+
283
+ > val1 /= val2;
284
+
285
+ > break;
286
+
287
+ > default:
288
+
289
+ > val1 = val2;
290
+
291
+ > break;
292
+
293
+ > }
294
+
295
+ >
296
+
297
+ > double result = Math.Truncate(val1 * 100.0) / 100.0;
298
+
299
+ >
300
+
301
+ > txtDisplay.Text = result.ToString();
302
+
303
+ > isFirst = true;
304
+
305
+ > }
306
+
307
+ > }
308
+
309
+ >
310
+
311
+ > }
312
+
313
+ ```