黑马程序员+Winform基础
- 控件：Button 按钮，TextBox 文本框， Label 标签，RadioButton 单选按钮，CheckButton 复选框 ，ListBox 列表框 ，PictureBox 图片框，ComboBox 下拉列表框
- 属性：Text：文本框中输入的值 ,Name:通过name来操作对象，Form.Text:窗体的标题，ForeColor:前景色，TextAlign:文本对齐，Image 图片，PasswordChar:密码文本 ，MultiLine 多行文本，Items 数据项，DropDownStyle:控制组合框的外观和功能，SelectItem 选中的项，SelectIndex 选中项的索引
- string.Format(“{0},你好”，textBox1.Text); //设置输出格式
- 方法：Form.Hide():对象隐藏,TextBox. AppendText()附加文本，
- 事件：Click:点击, SelectedIndexChanged 选择项发生改变
6．练习：求和
/// <summary>
/// 求和
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnAdd_Click(object sender, EventArgs e)
{
string num1 = txtnum1.Text;
string num2 = txtnum2.Text;
int i1,i2;
if (!int.TryParse(num1,out i1))//转换成int
{
MessageBox.Show("第一个数不合法！");
txtnum1.Text = "";//数字不合法，清空文本框
}
else if (int.TryParse(num2, out i2) == false)
{
MessageBox.Show("第二个数不合法！");
txtnum2.Text = "";
}
else
{//求和输出
txtsum.Text = (i1 + i2).ToString();
}
}
7. 练习：核对Email，分析出用户名和域名
/// <summary>
/// 核对Email，分析出用户名和域名
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void button1_Click(object sender, EventArgs e)
{
string email = txtEmail.Text;
string[] str = email.Split('@');
if (str.Length!=2)
{
MessageBox.Show("Email不合法");
txtEmail.Text = "";
}
else
{
MessageBox.Show(string.Format("用户名：{0} , 域名：{1}",str[0],str[1]));
}
}
8. 练习：两个数的累加
/// <summary>
/// 累加
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void button2_Click(object sender, EventArgs e)
{
string num1 = textBox1.Text;
string num2 = textBox2.Text;
int i1, i2,sum=0;
if (!int.TryParse(num1,out i1))
{
MessageBox.Show("第一个数非法");
textBox1.Text = "";
}
else if (!int.TryParse(num2,out i2))
{
MessageBox.Show("第二个数非法");
textBox1.Text = "";
}
else
{ //判断
if (i1>=i2)
{
MessageBox.Show("第一个数必须小于第二个数");
textBox1.Text = "";
textBox2.Text = "";
}
else
{//累加
for (int i = i1; i <= i2; i++)
{
sum += i;
}
MessageBox.Show(string.Format("{0}累加到{1}和为{2}", i1, i2, sum));
}
}
}
9 .练习：
/// <summary>
/// 查看图片（满18岁可查看）
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void button5_Click(object sender, EventArgs e)
{
string id = textBox4.Text;
//验证输入的身份证是否合法
if (id.Length!=18)
{
MessageBox.Show("身份证输入不合法");
textBox4.Text = "";
}
else
{//判断是否成年
if (DateTime.Now.Year-Convert.ToInt32(id.Substring(6,4))>18)
{
pictureBox1.Visible = true;
}
else
{
pictureBox1.Visible = false;
MessageBox.Show("年龄太小！");
}
}
}
10.练习：
/// <summary>
/// 向左移动
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void button3_Click(object sender, EventArgs e)
{
string str = textBox3.Text;
this.textBox3.Text = str.Substring(1)+str.Substring(0,1);
}
/// <summary>
/// 向右移动
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void button4_Click(object sender, EventArgs e)
{
string str = textBox3.Text;
this.textBox3.Text = str.Substring(str.Length-1)+str.Substring(0, str.Length - 1);
}
11.+=与appendText的区别
/// <summary>
/// 附加文本
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void button6_Click(object sender, EventArgs e)
{
//textBox5.Text += DateTime.Now+"\r\n";//用于数据量小
textBox5.AppendText(DateTime.Now.ToString()+"\n");//数据量大
}
12．练习：登录错三次不让再登录
/// <summary>
/// 登录，失败超过3次后退出
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private int errorTime = 0;
private void btnsubmit_Click(object sender, EventArgs e)
{
string userName = txtname.Text.Trim();
string pwd = txtpwd.Text.Trim();
if (userName.Equals("admin", StringComparison.OrdinalIgnoreCase)&&pwd.Equals("888888"))
{
MessageBox.Show("登录成功！");
}
else
{
errorTime++;//不能用局部变量，用类字段才可达到计数的功能
if (errorTime>=3)
{
MessageBox.Show("错误三次，不允许再登录！");
//this.Close();
Application.Exit();//退出程序
}
else
{
MessageBox.Show("登录失败！");
}
}
}