?
if
語句可以與 else
語句結(jié)合使用,在if中條件為 false
時(shí)執(zhí)行else中代碼
2)if......else if......else當(dāng)有多個(gè)條件需要判斷時(shí),可以使用 else if
進(jìn)行鏈?zhǔn)脚?/span>斷namespace _004_if語句
{
public partial class if語句 : Form
{
public if語句()
{
InitializeComponent();
}
//if else
private void btIfElse_Click(object sender, EventArgs e)
{
int a = 10;int b=20;
if (a>b)
{
MessageBox.Show("a>b");
}
else
{
MessageBox.Show("a<b");
}
}
//if else if
private void btIfElseif_Click(object sender, EventArgs e)
{
int week = int.Parse(this.txtWeek.Text);//將輸入內(nèi)容轉(zhuǎn)換為數(shù)值型
if(week==1)
{
MessageBox.Show("周1");
}
else if(week == 2)
{
MessageBox.Show("周2");
}
else if (week == 3)
{
MessageBox.Show("周3");
}
else if(week==4)
{
MessageBox.Show("周4");
}
else if (week == 5)
{
MessageBox.Show("周5");
}
else if ((week==6) || (week == 7))
{
MessageBox.Show("休息");
}
}
}
}
用于根據(jù)一個(gè)變量的值執(zhí)行不同的代碼塊。namespace _005_switch_case語句
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void btswitch_Click(object sender, EventArgs e)
{
int a = int.Parse(this.txtWeek.Text);//輸入的數(shù)值
switch (a)
{
case 1://a=1時(shí)
MessageBox.Show("周一"); break;
case 2:
MessageBox.Show("周二"); break;
case 3:
MessageBox.Show("周三"); break;
case 4:
MessageBox.Show("周四"); break;
case 5:
MessageBox.Show("周五"); break;
case 6:
MessageBox.Show("周六"); break;
default:
MessageBox.Show("周日"); break;
}
}
}
}
該文章在 2025/2/18 16:48:55 編輯過