#代码

namespace WindowsFormsApplication1 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { } private void label1_Click(object sender, EventArgs e) { } private void button1_Click(object sender, EventArgs e) { float num1 = 0; float num2 = 0; float result = 0; num1 = float.Parse(textBox1.Text); num2 = float.Parse(textBox2 .Text); result =num1 * num2 ; textBox3 .Text =result .ToString (); } private void botton2_click(object sender, EventArgs e) { textBox1.Text = ""; textBox2.Text = ""; textBox3.Text = ""; } } }

#效果

第一次作业第二题