Question

用C#做一个button，点击它使label显示textbox1与textbox2中数字之和0分

Answer 1

private void button1_Click(object sender, EventArgs e)
{
label1.Text = (Convert.ToDouble(textBox1.Text) +Convert.ToDouble(textBox2.Text)).ToString();
}

Answer 2

private void button1_Click(object sender, EventArgs e)
{
stirng x= textBox1.Text.Trim();
string y= textBox2.Text.Trim();
int Csun=int.Parse(x)+int.Parse(y);
if(Csun==0)
label1.Text =Csun.toString(); //等於零
else
label1.Text=Csun.toString(); //总和
}

Answer 3

private void button1_Click(object sender, EventArgs e)
{
label1.Text = (Convert.ToDouble(textBox1.Text.Trim()==""?"0":textBox1.Text.Trim()) +Convert.ToDouble(textBox2.Text.Trim()==""?"0":textBox2.Text.Trim())).ToString();
}

Answer 4

private void button1_Click(object sender, EventArgs e)
{
this.label.text=this.textBox1.Text + this.textBox2.Text;
}