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private void button1_Click(object sender, EventArgs e)
{
double num1;//第一个计算数;
double num2;//第二个计算数;
double result; //结果
num1 = double.Parse(txtnum1.Text);
num2 = double.Parse(txtnum2.Text);
if (txtnum1.Text!="")
{
if (cbbOperator.Text!="")
{
if (txtnum2.Text!="")
{
switch (cbbOperator.Text)
{
case "+":
result = num1 + num2;
break;
case "-":
result = num1 - num2;
break;
case "*":
result = num1 * num2;
break;
case "/":
if (double.Parse( txtnum2.Text) != 0)
{
result = num1 / num2;
}
else
{
MessageBox.Show("除数不能为0");
}
break;
case "%":
if (double.Parse( txtnum2.Text)!=0)
{
result = num1 % num2;
}
else
{
MessageBox.Show("除数不能为0");
}
break;
default:
MessageBox.Show("请选择运算符");
break;
}
}
else
{
MessageBox.Show("请输入第二个计算数");
}
}
else
{
MessageBox.Show("请输入运算符");
}
}
else
{
MessageBox.Show("请输入第一个计算数");
}
}
我想输入空值```它就给我爆了``不知道怎么改哦`
private void button1_Click(object sender, EventArgs e)
{
double num1=0;//第一个计算数;
double num2=0;//第二个计算数;
double result=0; //结果
bool gotNumber = true;
if (!double.TryParse(txtnum1.Text, out num1))
{
num1 = 0;
MessageBox.Show("请输入第一个计算数,注意格式");
gotNumber = false;
}
if (!double.TryParse(txtnum2.Text, out num2))
{
num2 = 0;
MessageBox.Show("请输入第二个计算数,注意格式");
gotNumber = false;
}
if (!gotNumber)
return;
num1 = double.Parse(txtnum1.Text);
num2 = double.Parse(txtnum2.Text);
if (cbbOperator.Text!=null)
{
switch (cbbOperator.Text)
{
case "+":
result = num1 + num2;
break;
case "-":
result = num1 - num2;
break;
case "*":
result = num1 * num2;
break;
case "/":
if (double.Parse( txtnum2.Text) != 0)
{
result = num1 / num2;
}
else
{
MessageBox.Show("除数不能为0");
}
break;
case "%":
if (double.Parse( txtnum2.Text)!=0)
{
result = num1 % num2;
}
else
{
MessageBox.Show("除数不能为0");
}
break;
default:
MessageBox.Show("请选择运算符");
break;
}
}
else
{
MessageBox.Show("请输入运算符");
}
txtResult.Text = result.ToString();
}
bool gotNumber = true;
if(!double.TryParse(txtnum1.Text, out num1))
{
num1 = 0;
MessageBox.Show("请输入第一个计算数,注意格式");
gotNumer = false;
}
if (!double.TryParse(textBox1.Text, out num2))
{
num2 = 0;
MessageBox.Shuw("请输入第二个计算数,注意格式");
gotNumber = false;
}
if(!gotNumber)
return;
if(!double.TryParse(textBox1.Text, out num1));
num1 = 0;
if (!double.TryParse(textBox1.Text, out num2))
num2 = 0;
try
{
num1 = double.Parse(txtnum1.Text);
num2 = double.Parse(txtnum2.Text);
}
catch (FormatException e1)
{
txtnum1.Text = e1.Message;
}