csharp_ATM之找回密码篇

1.先添加一行命名空间，如果没有这一行代码，下面的代码绝对会出错

using System.Data.SqlClient;`

public Form2()
      {
          InitializeComponent();
      }

      Form1 f01;
      public Form2(Form1 f1)//隐藏父窗体，然后通过but2 show出来
      {
          InitializeComponent();
          f01 = f1;
      }

2.为textBox3设置密码掩字符

private void textBox3_TextChanged(object sender, EventArgs e)
        {
            textBox3.PasswordChar = '*';
        }

3.验证卡号与凭证是否匹配

private void button1_Click(object sender, EventArgs e)
        {
            if (textBox1.Text == "" & textBox2.Text == "" & textBox3.Text == "")
            {
                MessageBox.Show("不能留空哦");
            }
            else
            {
                string count = "SERVER=.;DATABASE=OX;USER=SA;PWD=1;";
                //string sql= "update  server set pwd='" + textBox3.Text.Trim() + "'where sno='"+textBox1.Text+"'where sfz='"+textBox2.Text+"'";
                string sql = "update USERR set pwd='" + textBox3.Text + "'where  ID='" + textBox1.Text.Trim() + "'AND ID IN(SELECT ID FROM DATA WHERE SFZ='"+textBox2.Text+"')";
                //UPDATE USERR SET PWD='12' WHERE ID='123' AND  ID IN(SELECT ID FROM DATA WHERE SFZ='9876')
                SqlConnection con = new SqlConnection(count);//创建连接对象
                con.Open();
                SqlCommand cmd = new SqlCommand(sql, con);//创建操作对象
                if (cmd.ExecuteNonQuery()>0)
                {
                    MessageBox.Show("修改成功");
                    Form1 f1 = new Form1();
                    this.button1.Visible = true;
                    //this.button2.Visible = true;
                    this.textBox1.Visible = true;
                    this.textBox2.Visible = true;
                    this.label1.Visible = true;
                    this.label2.Visible = true;
                    this.label3.Visible = true;
                    f01.Hide();
                    f1.Show();
                }
                else
                {
                    MessageBox.Show("修改失败");
                }
            }
        }

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