WinForm05

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Students
{
    public partial class Frm_EditScore : Form
    {

        public Frm_Score fs = null;
        public Guid sid = Guid.Empty;
        public string sname = string.Empty;
        string connectionString = "server=localhost;database=Student;uid=sa;pwd=123123";
        public Frm_EditScore()
        {
            InitializeComponent();
        }
        private void dgv_Students_CellClick(object sender, DataGridViewCellEventArgs e)
        {
            txt_Sname.Text = dgv_Students.Rows[dgv_Students.CurrentRow.Index].Cells["col_SName"].Value.ToString();
            txt_Sid.Text = dgv_Students.Rows[dgv_Students.CurrentRow.Index].Cells["col_Sid"].Value.ToString();
            p_dgv.Visible = false;
        }

        private void Frm_Add_Load(object sender, EventArgs e)
        {
            ComboxDataBind();
            FindScoreBysid();
        }

        public void ComboxDataBind()
        {
            string queryName = txt_Sname.Text.Trim();
            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                conn.Open();
                StringBuilder sb = new StringBuilder();
                sb.Append(" select * from t_course");
                SqlCommand command = new SqlCommand(sb.ToString(), conn);
                SqlDataAdapter sda = new SqlDataAdapter(command);
                DataSet ds = new DataSet();
                sda.Fill(ds);
                cmb_Course.DataSource = ds.Tables[0];
                cmb_Course.ValueMember = "cid";
                cmb_Course.DisplayMember = "cname";
            }
        }

        public void FindScoreBysid()
        {
            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                conn.Open();
                StringBuilder sb = new StringBuilder();
                sb.Append("select * from t_score where sid = @sid");
                SqlCommand command = new SqlCommand(sb.ToString(),conn);
                command.Parameters.Add("@sid", sid);
                SqlDataReader sdr = command.ExecuteReader();
                if (sdr.HasRows)
                {
                    if (sdr.Read())
                    {
                        txt_Sid.Text = sid.ToString();
                        txt_Sname.Text = sname;
                        cmb_Course.SelectedValue = sdr["cid"];
                        nup_Score.Value = decimal.Parse(sdr["score"].ToString());
                        txt_Sname.Enabled = false;
                        cmb_Course.Enabled = false;
                        btn_Select.Visible = false;
                    }
                }
            }
        }


        private void btn_Select_Click(object sender, EventArgs e)
        {
            p_dgv.Visible = true;
            using (SqlConnection con = new SqlConnection(connectionString))
            {
                con.Open();
                StringBuilder sb = new StringBuilder();
                sb.Append("select sname,sage,sid,saddress,ssex from t_Students");
                sb.Append(" where 1=1 ");
                if (txt_Sname.Text.Trim().Length > 0)
                {
                    sb.Append("and Sname like '%" + txt_Sname.Text.Trim() + "%'");
                }
                SqlDataAdapter sda = new SqlDataAdapter(sb.ToString(), con);
                DataSet ds = new DataSet();
                sda.Fill(ds);
                DataTable dt = ds.Tables[0];
                dgv_Students.DataSource = dt;
            }
        }

        private void btn_Save_Click(object sender, EventArgs e)
        {
            string sql = string.Empty;
            if(sid == Guid.Empty)
            {
                sql = "insert into t_score values(NEWID(),@cid,@uid,@score)";
            }
            else
            {
                sql = "update t_score set score = @score where sid = @sid";
            }
            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                conn.Open();
                SqlCommand command = new SqlCommand(sql, conn);
                if (sid == Guid.Empty)//增加
                {
                    command.Parameters.Add("@cid", cmb_Course.SelectedValue);
                    command.Parameters.Add("@uid", txt_Sid.Text.Trim());
                }
                else//修改
                {
                    command.Parameters.Add("@sid",sid);
                }
                
                command.Parameters.Add("@score", nup_Score.Value.ToString());
                int index = command.ExecuteNonQuery();
                if (index > 0)
                {
                    MessageBox.Show("操作成功!!!", "操作提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    //增加成功以后刷新父窗体
                    if (fs != null)
                    {
                        fs.DataBind();
                    }
                }
                else
                {
                    MessageBox.Show("操作成功!!!", "操作提示", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
        }

        private void btn_Cancel_Click(object sender, EventArgs e)
        {
            this.Close();
        }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Students
{
    public partial class Frm_Score : Form
    {
        string connectionString = "server=localhost;database=Student;uid=sa;pwd=123123";
        public Frm_Score()
        {
            InitializeComponent();
        }

        private void Frm_Score_Load(object sender, EventArgs e)
        {
            DataBind();
           
            //打开所有的节点
            tv_Menu.ExpandAll();
        }

        private void btn_Query_Click(object sender, EventArgs e)
        {
            DataBind();
        }

        private void btn_Add_Click(object sender, EventArgs e)
        {
            Frm_EditScore fas = new Frm_EditScore();
            fas.fs = this;
            fas.ShowDialog();
        }

        private void btn_Edit_Click(object sender, EventArgs e)
        {
            if (dgv_Score.SelectedRows.Count > 0)
            {
                Frm_EditScore fe = new Frm_EditScore();
                fe.Text = "编辑成绩";
                fe.fs = this;
                fe.sid = Guid.Parse(dgv_Score.Rows[dgv_Score.CurrentRow.Index].Cells["col_sid"].Value.ToString());
                fe.sname = dgv_Score.Rows[dgv_Score.CurrentRow.Index].Cells["col_sname"].Value.ToString();
                fe.ShowDialog();
            }
            else
            {
                MessageBox.Show("请选择需要编辑的数据行!!!", "操作提示", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void Remove_Click(object sender, EventArgs e)
        {
            if (dgv_Score.SelectedRows.Count > 0)
            {
                DialogResult dr = MessageBox.Show("你确定要删除当前选中行吗？", "操作提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Information);
                if (dr == DialogResult.OK)
                {
                    using (SqlConnection conn = new SqlConnection(connectionString))
                    {
                        conn.Open();
                        SqlCommand command = new SqlCommand("delete from t_score where sid = @sid",conn);
                        command.Parameters.Add("@sid", dgv_Score.Rows[dgv_Score.CurrentRow.Index].Cells["col_sid"].Value.ToString());
                        int index = command.ExecuteNonQuery();
                        if (index > 0)
                        {
                            MessageBox.Show("操作成功", "操作提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                            DataBind();
                        }
                        else
                        {
                            MessageBox.Show("操作失败", "操作提示", MessageBoxButtons.OK, MessageBoxIcon.Error);
                        }

                    }
                }
            }
            else
            {
                MessageBox.Show("你确定要删除当前选中行吗？", "操作提示", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }

        private void dgv_Score_DataBindingComplete(object sender, DataGridViewBindingCompleteEventArgs e)
        {
            dgv_Score.ClearSelection();
            for (int i = 0; i < dgv_Score.Rows.Count; i++)
            {
                if (i % 2 == 0)
                {
                    dgv_Score.Rows[i].DefaultCellStyle.BackColor = Color.Pink;
                }
            }
        }

        private void tv_Menu_AfterSelect(object sender, TreeViewEventArgs e)
        {
            if (tv_Menu.SelectedNode.Level == 2)
            {
                DataView dv = null;
                if(dgv_Score.DataSource is DataTable)
                {
                    DataTable dt = dgv_Score.DataSource as DataTable;
                    dv = new DataView(dt);
                }
                else
                {
                    dv = dgv_Score.DataSource as DataView;
                }
                string str = tv_Menu.SelectedNode.Text.Trim();
                //进行数据的筛选
                dv.RowFilter = "ssex='" +str+ "'";
                //根据列来排序
                dv.Sort = "sage desc";
                dgv_Score.DataSource = dv;
            }
        }

        #region 自定义的方法

        public void DataBind()
        {
            string queryName = txt_QueryName.Text.Trim();
            StringBuilder sb = new StringBuilder();
            sb.Append(" select course.cname,score.score,score.sid,student.sname,student.sage,student.ssex from t_students student");
            sb.Append(" inner join t_score score on student.sid=score.uid");
            sb.Append(" inner join t_course course on course.cid = score.cid");
            if (queryName.Length > 0)
            {
                sb.Append(" where student.sname like @sname");
            }
            using (SqlConnection conn = new SqlConnection(connectionString))
            {
                conn.Open();
                SqlCommand command = new SqlCommand(sb.ToString(), conn);
                if (queryName.Length > 0)
                {
                    command.Parameters.Add("@sname","%" + queryName + "%");
                }
                SqlDataAdapter sda = new SqlDataAdapter(command);
                DataSet ds = new DataSet();
                sda.Fill(ds);
                dgv_Score.DataSource = ds.Tables[0];
            }
        }
        #endregion
    }
}