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;

namespace?BMI
{
????public?partial?class?Form1?:?Form
????{
????????public?Form1（）
????????{
????????????InitializeComponent（）;
????????}
????????
????????private?void?label1_Click（object?sender?EventArgs?e）
????????{

????????}
????????//?KeyPressEventArgs?按下鍵時對鍵進行計數，并在每次按鍵后顯示結果。?Handled?然后，將設置為?true，以防止操作系統進一步處理該鍵。
????????private?void?textBox1_TextChanged（object?sender?EventArgs?e）
????????{

????????}

????????private?void?textBox3_TextChanged（object?sender?EventArgs?e）
????????{
????????????
????????}

????????private?void?button1_Click（object?sender?EventArgs?e）
????????{
????????????double?a;
????????????a?=?Convert.ToDouble（textBox2.Text）?/?Convert.ToDouble（textBox1.Text）?/?Convert.ToDouble（textBox1.Text）;
????????????textBox3.Text?=?Convert.ToString（a）;
????????????if?（a?>?28.0）
????????????{
????????????????textBox4.Text?=?“肥胖“;
????????????????this.pictureBox2.Load（“.\\img\\沙拉.png“）;//相對路徑，從生成的可執行文件所在處算根目錄
????????????}
????????????if?（a?????????????{
????????????????textBox4.Text?=?“偏瘦“;
????????????????this.pictureBox2.Load（“.\\img\\牛奶.png“）;
????????????}
????????????if?（a?>?18.5?&&?a?????????????{
????????????????textBox4.Text?=?“正常“;
????????????????this.pictureBox2.Load（“.\\img\\正常.png“）;
????????????}
????????????if?（a?>?24.0&&?a????????????{
????????????????textBox4.Text?=?“過重“;
????????????????this.pictureBox2.Load（“.\\img\\蔬菜.png“）;
????????????}
????????}
????????//點擊輸入框，在屬性欄上的事件中添加keypress事件
????????//KeyChar鍵值
????????//object?sender:表示觸發事件的控件對象
????????//KeyPressEventArgs?e：表示事件數據的類的基類
????????private?void?keypressed（object?sender?KeyPressEventArgs?e）
????????{
????????????//數字8是退格鍵的ASCII碼，0X2E即十進制46，是符號‘.’的ASCII編碼
????????????//Char.IsDigit（parameter）函數的功能是判斷字符是否屬于十進制數字類別。
????????????if?（e.KeyChar?!=?8?&&?!Char.IsDigit（e.KeyChar）?&&?e.KeyChar?!=?0x2E）
????????????{
????????????????e.Handled?=?true;
????????????}
????????????//當先輸入的是‘.‘，可以使用退格鍵
????????????if?（e.KeyChar?==?‘.‘）???
????????????{
????????????????//as運算符用于將表達式顯式轉換為給定類型（如果其運行時類型與該類型兼容）
????????????????TextBox?tb?=?sender?as?TextBox;
????????????????//當先輸入的為符號‘.’時，文本框顯示的是“0.”
????????????????if?（tb.Text?==?““）
????????????????{
????????????????????tb.Text?=?“0.“;
????????????????????//select（parameter1parameter2）函數選擇文本框中的文本范圍
????????????????????//參數1和參數2?分別表示文本的起始和結束位置。
????????????????????tb.Select（tb.Text.Length?0）;
????????????????????e.Handled?=?true;
????????????????}
????????????}
????????}

????????private?void?textBox2_TextChanged（object?sender?EventArgs?e）
????????{

????????}

????????private?void?Form1_Load（object?sender?EventArgs?e）
????????{

????????}

????????private?void?label4_Click（object?sender?Eve

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2020-09-15?10:14??BMI\
?????目錄???????????0??2020-09-11?14:54??BMI\.vs\
?????目錄???????????0??2020-09-11?14:54??BMI\.vs\BMI\
?????目錄???????????0??2020-09-11?14:54??BMI\.vs\BMI\v16\
?????文件???????40448??2020-09-15?10:14??BMI\.vs\BMI\v16\.suo
?????文件?????????189??2020-09-11?14:54??BMI\App.config
?????目錄???????????0??2020-09-11?14:54??BMI\bin\
?????目錄???????????0??2020-09-15?10:03??BMI\bin\Debug\
?????文件???????17920??2020-09-15?10:14??BMI\bin\Debug\BMI.exe
?????文件?????????189??2020-09-11?14:54??BMI\bin\Debug\BMI.exe.config
?????文件???????34304??2020-09-15?10:14??BMI\bin\Debug\BMI.pdb
?????目錄???????????0??2020-09-14?17:33??BMI\bin\Debug\img\
?????文件???????48436??2020-09-14?17:28??BMI\bin\Debug\img\牛奶.png
?????文件??????137550??2020-09-14?17:31??BMI\bin\Debug\img\沙拉.png
?????文件??????108595??2020-09-14?17:29??BMI\bin\Debug\img\蔬菜.png
?????文件??????131279??2020-09-14?17:30??BMI\bin\Debug\img\正常.png
?????文件????????3594??2020-09-11?15:22??BMI\BMI.csproj
?????文件????????1110??2020-09-11?14:54??BMI\BMI.sln
?????文件????????3785??2020-09-15?10:14??BMI\Form1.cs
?????文件???????10056??2020-09-15?09:47??BMI\Form1.Designer.cs
?????文件???????14882??2020-09-15?09:47??BMI\Form1.resx
?????目錄???????????0??2020-09-11?14:54??BMI\obj\
?????目錄???????????0??2020-09-14?17:27??BMI\obj\Debug\
?????文件??????????42??2020-09-11?15:22??BMI\obj\Debug\BMI.csproj.CoreCompileInputs.cache
?????文件?????????415??2020-09-15?10:14??BMI\obj\Debug\BMI.csproj.FileListAbsolute.txt
?????文件????????1012??2020-09-15?09:47??BMI\obj\Debug\BMI.csproj.GenerateResource.cache
?????文件?????????424??2020-09-15?09:47??BMI\obj\Debug\BMI.csprojAssemblyReference.cache
?????文件???????17920??2020-09-15?10:14??BMI\obj\Debug\BMI.exe
?????文件????????6328??2020-09-15?09:47??BMI\obj\Debug\BMI.Form1.resources
?????文件???????34304??2020-09-15?10:14??BMI\obj\Debug\BMI.pdb
?????文件?????????180??2020-09-11?15:22??BMI\obj\Debug\BMI.Properties.Resources.resources
............此處省略10個文件信息