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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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コードをインデント

2020/03/12 08:09

投稿

Gunjirk
Gunjirk

スコア23

title CHANGED
File without changes
body CHANGED
@@ -19,137 +19,139 @@
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  不明点あれば、何でも答えます。
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- using System;
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- using System.Collections.Generic;
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- using System.ComponentModel;
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- using System.Data;
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- using System.Drawing;
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- using System.Linq;
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- using System.Text;
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- using System.Threading.Tasks;
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- using System.Windows.Forms;
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22
 
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- namespace WindowsFormsApp1
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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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- public Form1()
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- {
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- InitializeComponent();
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- }
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-
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- bool isFirst = true;
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- double val1 = 0;
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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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- private void btnNumber_Click(object sender, EventArgs e)
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- {
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- if (isFirst)
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- {
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- txtDisplay.Text = "";
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- isFirst = false;
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- }
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- String text = txtDisplay.Text + ((Button)sender).Text;
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-
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- //文字列　-> 数値
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- double d = Convert.ToDouble(text);
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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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- String text2 = d.ToString();
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- txtDisplay.Text = text2;
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- }
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-
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- enum sign { blank, ADD, SUB, MUL, DIV };
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- sign exec = sign.blank;
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-
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- //クリア
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- private void button_clear_Click(object sender, EventArgs e)
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- {
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- exec = sign.blank;
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- txtDisplay.Text = "0";
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- val1 = 0;
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- isFirst = true;
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- }
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-
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- //小数点
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- private void button_dot_Click(object sender, EventArgs e)
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- {
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- //小数点の重複チェック
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- if(txtDisplay.Text.IndexOf(".") >= 1)
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- {
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- //すでに小数点がある
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- return;
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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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- //足し算。
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- private void button_tasu_Click(object sender, EventArgs e)
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- {
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- if (!isFirst) calc();
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- exec = sign.ADD;
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- }
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-
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- //引き算。
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- private void button_hiku_Click(object sender, EventArgs e)
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- {
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- if (!isFirst) calc();
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- exec = sign.SUB;
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- }
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-
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- //掛け算。
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- private void button_kakuru_Click(object sender, EventArgs e)
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- {
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- if (!isFirst) calc();
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- exec = sign.MUL;
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- }
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-
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- //割り算。
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- private void button_waru_Click(object sender, EventArgs e)
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- {
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- if (!isFirst) calc();
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- exec = sign.DIV;
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- }
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-
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- //イコール。
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- private void button_wa_Click(object sender, EventArgs e)
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- {
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- calc();
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- }
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-
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- private void calc()
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- {
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- double val2 = Convert.ToDouble(txtDisplay.Text);
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- switch (exec)
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- {
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- case sign.ADD:
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- val1 += val2;
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- break;
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- case sign.SUB:
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- val1 -= val2;
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- break;
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- case sign.MUL:
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- val1 *= val2;
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- break;
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- case sign.DIV:
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- val1 /= val2;
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- break;
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- default:
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- val1 = val2;
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- break;
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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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- txtDisplay.Text = result.ToString();
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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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+ > using System;
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+ > using System.Collections.Generic;
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+ > using System.ComponentModel;
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+ > using System.Data;
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+ > using System.Drawing;
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+ > using System.Linq;
29
+ > using System.Text;
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+ > using System.Threading.Tasks;
31
+ > using System.Windows.Forms;
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+ >
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+ > namespace WindowsFormsApp1
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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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+ > public Form1()
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+ > {
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+ > InitializeComponent();
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+ > }
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+ >
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+ > bool isFirst = true;
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+ > double val1 = 0;
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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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+ > private void btnNumber_Click(object sender, EventArgs e)
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+ > {
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+ > if (isFirst)
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+ > {
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+ > txtDisplay.Text = "";
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+ > isFirst = false;
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+ > }
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+ > String text = txtDisplay.Text + ((Button)sender).Text;
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+ >
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+ > //文字列　-> 数値
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+ > double d = Convert.ToDouble(text);
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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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+ > String text2 = d.ToString();
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+ > txtDisplay.Text = text2;
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+ > }
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+ >
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+ > enum sign { blank, ADD, SUB, MUL, DIV };
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+ > sign exec = sign.blank;
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+ >
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+ > //クリア
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+ > private void button_clear_Click(object sender, EventArgs e)
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+ > {
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+ > exec = sign.blank;
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+ > txtDisplay.Text = "0";
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+ > val1 = 0;
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+ > isFirst = true;
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+ > }
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+ >
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+ > //小数点
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+ > private void button_dot_Click(object sender, EventArgs e)
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+ > {
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+ > //小数点の重複チェック
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+ > if(txtDisplay.Text.IndexOf(".") >= 1)
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+ > {
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+ > //すでに小数点がある
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+ > return;
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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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+ > //足し算。
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+ > private void button_tasu_Click(object sender, EventArgs e)
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+ > {
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+ > if (!isFirst) calc();
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+ > exec = sign.ADD;
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+ > }
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+ >
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+ > //引き算。
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+ > private void button_hiku_Click(object sender, EventArgs e)
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+ > {
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+ > if (!isFirst) calc();
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+ > exec = sign.SUB;
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+ > }
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+ >
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+ > //掛け算。
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+ > private void button_kakuru_Click(object sender, EventArgs e)
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+ > {
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+ > if (!isFirst) calc();
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+ > exec = sign.MUL;
112
+ > }
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+ >
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+ > //割り算。
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+ > private void button_waru_Click(object sender, EventArgs e)
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+ > {
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+ > if (!isFirst) calc();
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+ > exec = sign.DIV;
119
+ > }
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+ >
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+ > //イコール。
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+ > private void button_wa_Click(object sender, EventArgs e)
123
+ > {
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+ > calc();
125
+ > }
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+ >
127
+ > private void calc()
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+ > {
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+ > double val2 = Convert.ToDouble(txtDisplay.Text);
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+ > switch (exec)
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+ > {
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+ > case sign.ADD:
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+ > val1 += val2;
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+ > break;
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+ > case sign.SUB:
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+ > val1 -= val2;
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+ > break;
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+ > case sign.MUL:
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+ > val1 *= val2;
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+ > break;
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+ > case sign.DIV:
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+ > val1 /= val2;
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+ > break;
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+ > default:
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+ > val1 = val2;
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+ > break;
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+ > }
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+ >
149
+ > double result = Math.Truncate(val1 * 100.0) / 100.0;
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+ >
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+ > txtDisplay.Text = result.ToString();
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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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+ ```