if (textBox1.Text == ""||textBox2.Text == ""||textBox3.Text == "")             {                 if (MessageBox.Show("      您输入的信息不完整！     ，是否关闭窗口", "提示",                           MessageBoxButtons.YesNo, MessageBoxIcon.Question) ==                           DialogResult.Yes)                 {                     this.Close();                                     }             }             else  if(textBox2.Text!=textBox3.Text)             {                 if (MessageBox.Show("     您的新密码输入错误！     ，是否关闭窗口", "提示",                           MessageBoxButtons.YesNo, MessageBoxIcon.Question) ==                           DialogResult.Yes)                 {                     this.Close();                                     }             }             else if (textBox1.Text != "")             {                 string constr = "integrated security=SSPI;data source=.;persist security info=False;initial catalog=anne";                 SqlConnection sqlConnection1 = new SqlConnection(constr);                 string sq1 = "select 密码 from 密码表 where 用户名='admin'";                 SqlDataAdapter sqlDataAdapter1 = new SqlDataAdapter(sq1, sqlConnection1);                 DataSet dt1 = new DataSet();                 sqlDataAdapter1.Fill(dt1, "密码表");                 string sq2= textBox1.Text;                 string sq3 = (string)dt1.Tables["密码表"].Rows[0]["密码"];                 if (sq2.Equals(sq3.Trim()) && textBox2.Text == textBox3.Text)                 {                     string constr1 = "integrated security=SSPI;data source=.;persist security info=False;initial catalog=anne";                     string sq4 = "update 密码表 set 密码='" + textBox2.Text + "' where 密码='" + textBox1.Text + "'";                     SqlConnection sqlConnection = new SqlConnection(constr1);                     sqlConnection.Open();                     SqlCommand cd = new SqlCommand(sq4, sqlConnection);                     SqlDataReader sr = cd.ExecuteReader();                     MessageBox.Show("    密码已修改成功    ", "提  醒");