This class can be use to perform basic mathematical operations
/* thi class have a function on performing some basic operations in c# addition subtraction
multplication and division having only one function
*/
class cls_MDAS
{
/// <summary>
/// simple mdas have a parameter of first_num, last_num and opt this firstnum and second num must be a number
/// </summary>
/// <param name="firstNum"></param>
/// <param name="lastNum"></param>
/// <param name="opt"></param>
/// <returns></returns>
public string simple_mdas(int firstNum, int lastNum,string opt)
{
string result = "";// declaration of a variable `
switch (opt) // checks the value of opt
{
case "+":
// if opt equals to + then this code will execute
result = (firstNum + lastNum) .ToString();
break;
case "-":
// if opt equals to - then this code will execute
result = (firstNum - lastNum) .ToString();
break;
case "*":
// if opt equals to * then this code will execute
result = (firstNum * lastNum) .ToString();
break;
case "/":
// if opt equals to / then this code will execute
//checks if first num =0
if (firstNum != 0)
{
if (firstNum >= lastNum)
{
result = (firstNum / lastNum).ToString();
}
else
{
result = "first number must be greater than the second number";
}
}
else
{
result = "first number must not be equal to 0";
}
break;
default:
result = "Please select from the choices";
}
//returns a result if a result base from the operations above or an error
return result;
}
}
to call the classes from the function you need to include this code on a combobox event SelectedIndexChanged
try is used when an expected error might be encounter catch method will be executed if theirs an error
try
{
cls_MDAS cls = new cls_MDAS(); // instantiation of cls_MDAS for us to use the function that are declared public
string main_result=cls.simple_mdas(int.Parse(txtFirstNumber.Text), int.Parse(txtSecondNumber.Text),cbochoices.Text);
MessageBox.Show(main_result);
// string main_result value wull hold the returned value of function simple_mdas depending on the parameter u send
}
catch
{
MessageBox.Show("input some number");
}
