private void button1_Click(object sender, EventArgs e)
{
//Get the value of the text box
string txt1 = textBox1 .Text;
string txt2 = textBox2.Text;
string txt3 = textBox3.Text;
//Define the integer variable stored during conversion (if Floating point type can be replaced by yourself)
int num1 = 0;
int num2 = 0;
int num3 = 0;
int result = 0;//The smallest number
//int.TryParse will return whether txt1 can be converted to int type. If it can be converted, the value will be assigned to num1
if ( !int.TryParse(txt1, out num1)) //If txt1 cannot be converted to int type
{
MessageBox.Show("The first text box is not a valid integer") ;
return;
}
result = num1;//Because it is the first value, it is assigned directly
if ( !int.TryParse(txt2, out num2)) //If txt2 cannot be converted to int type
{
MessageBox.Show("The second text box is not a valid integer") ;
return;
}
if (num2 < result) //If num2 is less than the current smallest number
{
result = num2;//The current smallest number is changed to num2
}
if (!int.TryParse(txt3, out num3)) //If txt3 cannot be converted to int type
{
MessageBox.Show("The third text box is not a valid integer");
return;
}
if (num3 < result) //If num3 is less than the current smallest number
{
result = num3;//The current smallest number number, change to num3
}
//Display the final smallest number
label4.Text = "Among the three text boxes, the smallest number is" + result;
}