<script language="javascript">
function GetSum() {
    var txt1 = document.getElementById('txt1')
    var txt2 = document.getElementById('txt2')
    var total = txt1.value + txt2.value;
    alert(total);
}
</script>
<asp:TextBox ID="txt1" runat="server" ></asp:TextBox>
<asp:TextBox ID="txt2" runat="server" ></asp:TextBox>
<input type="button" Text="Add" onclick="GetSum()" />

使用System.Windows.Forms;



class program

{

static void Main（string [] args）

{

Console.WriteLine（仅在数字中输入输入1： ）;

int input1 = Convert.ToInt32（Console.ReadLine（））;



Console.WriteLine（输入输入2 in仅限数字：）;

int input2 = Convert.ToInt32（Console.ReadLine（））;



int sum = input1 + input2 ;

MessageBox.Show（sum.ToString（），信息）;

}

}

using System.Windows.Forms;

class Program
{
static void Main(string[] args)
{
Console.WriteLine("Enter Input 1 in Number Only :");
int input1 = Convert.ToInt32(Console.ReadLine());

Console.WriteLine("Enter Input 2 in Number Only :");
int input2 = Convert.ToInt32(Console.ReadLine());

int sum = input1 + input2;
MessageBox.Show(sum.ToString(), "Information");
}
}

这是一个例子（一定要添加对System.Windows.Forms的引用）

Here's an example (be sure to add a reference to System.Windows.Forms)

使用System.Windows.Forms;



class Program

{

static void Main（string [] args）

{

Console.WriteLine（仅在数字中输入输入1：）;

int in put1 = Convert.ToInt32（Console.ReadLine（））;



Console.WriteLine（仅在数字中输入输入2：）;

int input2 = Convert.ToInt32（Console.ReadLine（））;



int sum = input1 + input2;

MessageBox.Show （sum.ToString（），信息）;

}

}

using System.Windows.Forms;

class Program
{
static void Main(string[] args)
{
Console.WriteLine("Enter Input 1 in Number Only :");
int input1 = Convert.ToInt32(Console.ReadLine());

Console.WriteLine("Enter Input 2 in Number Only :");
int input2 = Convert.ToInt32(Console.ReadLine());

int sum = input1 + input2;
MessageBox.Show(sum.ToString(), "Information");
}
}