private void button17_Click(object sender, EventArgs e)
{
if (i == 0)
this.textBox1.Text = Convert.ToString("0");
else
switch(str2)
{
case "+":
this.textBox1.Text = Convert.ToString(val3 = val2 + val1);
break;
case "-":
this.textBox1.Text = Convert.ToString(val3 = val2 - val1);
break;
case "/":
{
if (val1 == 0)
this.textBox1.Text = "Error";
else
this.textBox1.Text = Convert.ToString(val3 = val2 / val1);
break;
}
case "*":
this.textBox1.Text = Convert.ToString(val3 = val2 * val1);
break;
default:
this.textBox1.Text = "Error"; break;
}
}
{
if (i == 0)
this.textBox1.Text = Convert.ToString("0");
else
switch(str2)
{
case "+":
this.textBox1.Text = Convert.ToString(val3 = val2 + val1);
break;
case "-":
this.textBox1.Text = Convert.ToString(val3 = val2 - val1);
break;
case "/":
{
if (val1 == 0)
this.textBox1.Text = "Error";
else
this.textBox1.Text = Convert.ToString(val3 = val2 / val1);
break;
}
case "*":
this.textBox1.Text = Convert.ToString(val3 = val2 * val1);
break;
default:
this.textBox1.Text = "Error"; break;
}
}
this.textBox1.Text = Convert.ToString(val3); 这样试试
哥们, 你说反了吧?建议在 switch(str2) 前加一条语句判断一下str2的值是否有与case分支相同的, 再查找原因。
从那里来的吗要说明他的来源。。要不程序不知它是做什么的。就只好default了啊。
只能是 如 int char 等