SQLHelper连接数据库示例类
[实例简介] 连接sql数据库 类 [核心代码]using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Configuration;using System.Data.SqlClient;using System.Data; namespace Itcast.Cn{ public static class SqlHelper { private static readonly string conStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString; //执行增删改的 public static int ExecuteNonQuery(string sql, CommandType cmdType, params SqlParameter[] pms) { using (SqlConnection con = new SqlConnection(conStr)) { using (SqlCommand cmd = new SqlCommand(sql, con)) { cmd.CommandType = cmdType; if (pms != null) { cmd.Parameters.AddRange(pms); } con.Open(); return cmd.ExecuteNonQuery(); } } } //封装一个执行返回单个值的方法 public static object ExecuteScalar(string sql, CommandType cmdType, params SqlParameter[] pms) { using (SqlConnection con = new SqlConnection(conStr)) { using (SqlCommand cmd = new SqlCommand(sql, con)) { cmd.CommandType = cmdType; if (pms != null) { cmd.Parameters.AddRange(pms); } con.Open(); return cmd.ExecuteScalar(); } } } //返回SqlDataReader对象的方法 public static SqlDataReader ExecuteReader(string sql, CommandType cmdType, params SqlParameter[] pms) { SqlConnection con = new SqlConnection(conStr); using (SqlCommand cmd = new SqlCommand(sql, con)) { cmd.CommandType = cmdType; if (pms != null) { cmd.Parameters.AddRange(pms); } try { con.Open(); return cmd.ExecuteReader(CommandBehavior.CloseConnection); } catch (Exception) { con.Close(); con.Dispose(); throw; } } } //封装一个返回DataTable的方法 public static DataTable ExecuteDataTable(string sql, CommandType cmdType, params SqlParameter[] pms) { DataTable dt = new DataTable(); using (SqlDataAdapter adapter = new SqlDataAdapter(sql, conStr)) { adapter.SelectCommand.CommandType = cmdType; if (pms != null) { adapter.SelectCommand.Parameters.AddRange(pms); } adapter.Fill(dt); } return dt; } //封装一个带事务的执行Sql语句的方法 public static void ExecuteNonQueryTran(List list) { using (SqlConnection con = new SqlConnection(conStr)) { using (SqlCommand cmd = con.CreateCommand()) { con.Open(); using (SqlTransaction trans = con.BeginTransaction()) { cmd.Transaction = trans; try { foreach (var SqlObject in list) { cmd.CommandText = SqlObject.Sql; if (SqlObject.Parameters != null) { cmd.Parameters.AddRange(SqlObject.Parameters); } cmd.CommandType = SqlObject.CmdType; cmd.ExecuteNonQuery(); cmd.Parameters.Clear(); } trans.Commit(); } catch (Exception) { trans.Rollback(); } } } } } } public class SqlAndParameter { public string Sql { get; set; } public SqlParameter[] Parameters { get; set; } public CommandType CmdType { get; set; } }}
- 2015-04-01下载
- 积分：1
winform DataGridViewRowStyle 常见用法实例源码下载 有图
DataGridViewRowStyle 核心用法 截图： 核心代码：using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;namespace TestDataGridViewRowStyle{ public partial class Form1 : Form { //定义两种行样式 private DataGridViewCellStyle m_RowStyleNormal; private DataGridViewCellStyle m_RowStyleAlternate; //成绩单DataTable private DataTable m_GradeTable; public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { this.dgvGrade.AutoGenerateColumns = false; this.SetRowStyle(); this.BindData(); } /// /// 设置行样式 /// private void SetRowStyle() { //可根据需要设置更多样式属性，如字体、对齐、前景色、背景色等 this.m_RowStyleNormal = new DataGridViewCellStyle(); this.m_RowStyleNormal.BackColor = Color.LightBlue; this.m_RowStyleNormal.SelectionBackColor = Color.LightSteelBlue; this.m_RowStyleAlternate = new DataGridViewCellStyle(); this.m_RowStyleAlternate.BackColor = Color.LightGray; this.m_RowStyleAlternate.SelectionBackColor = Color.LightSlateGray; } /// /// 绑定数据 /// private void BindData() { //建立一个DataTable并填充数据，然后绑定到DataGridView控件上 m_GradeTable = new DataTable(); m_GradeTable.Columns.Add("Class", typeof(string)); m_GradeTable.Columns.Add("Name", typeof(string)); m_GradeTable.Columns.Add("Grade", typeof(int)); m_GradeTable.Rows.Add(new string[] { "Class1", "Jim", "89" }); m_GradeTable.Rows.Add(new string[] { "Class1", "Jack", "77" }); m_GradeTable.Rows.Add(new string[] { "Class1", "Bill", "91" }); m_GradeTable.Rows.Add(new string[] { "Class2", "Tom", "58" }); m_GradeTable.Rows.Add(new string[] { "Class2", "Rose", "95" }); m_GradeTable.Rows.Add(new string[] { "Class3", "Peter", "64" }); m_GradeTable.Rows.Add(new string[] { "Class3", "David", "82" }); m_GradeTable.Rows.Add(new string[] { "Class3", "Eric", "68" }); m_GradeTable.Rows.Add(new string[] { "Class3", "Lily", "79" }); this.bdsGrade.DataSource = m_GradeTable; } private void dgvDataTable_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e) { //在此对行样式进行设置 if (e.ColumnIndex == this.dgvGrade.Columns["ColumnClass"].Index)//根据班级设置行样式 { DataGridViewRow CurrentRow = this.dgvGrade.Rows[e.RowIndex]; CurrentRow.HeaderCell.Value = Convert.ToString(e.RowIndex 1);//显示行号，也可以设置成显示其他信息 //CurrentRow.HeaderCell.ToolTipText = "当前第" Convert.ToString(e.RowIndex 1) "行";//设置ToolTip信息 //以下为根据上一行内容判断所属组的效果 if (e.RowIndex == 0)//首行必须特殊处理，将其设置为常规样式 { CurrentRow.DefaultCellStyle = this.m_RowStyleNormal; } else { //判断和上一行是否属于同一个班级，如果是则设置相同样式，否则设置另一种样式 //需要定义两个DataGridViewCellStyle，用于交替显示，也可以根据需要隐藏一些和上一行重复的信息 //这里当两行是同一个班级时，将下一行的班级信息隐藏掉，选中时则显示班级信息 if (CurrentRow.Cells[e.ColumnIndex].Value != DBNull.Value && CurrentRow.Cells[e.ColumnIndex].Value != null && CurrentRow.Cells[e.ColumnIndex].Value.ToString() == this.dgvGrade.Rows[e.RowIndex - 1].Cells[e.ColumnIndex].Value.ToString()) { CurrentRow.DefaultCellStyle = this.dgvGrade.Rows[e.RowIndex - 1].DefaultCellStyle;//设置和上一行的样式相同 CurrentRow.Cells[e.ColumnIndex].Style.ForeColor = CurrentRow.DefaultCellStyle.BackColor;//用前景色隐藏信息 //如果需要选中时显示完整信息则注释该下面一行 //CurrentRow.Cells[e.ColumnIndex].Style.SelectionForeColor = CurrentRow.DefaultCellStyle.SelectionBackColor;//选中时也使前景色等于背景色，将文字隐藏掉 } else//当前行和上一行不属于同一个班级时 { if (this.dgvGrade.Rows[e.RowIndex - 1].DefaultCellStyle == this.m_RowStyleNormal)//根据上一行的样式设置当前行的样式 CurrentRow.DefaultCellStyle = this.m_RowStyleAlternate; else CurrentRow.DefaultCellStyle = this.m_RowStyleNormal; } }//if(e.RowIndex == 0) } else if (e.ColumnIndex == this.dgvGrade.Columns["ColumnGrade"].Index)//根据成绩设置单元格样式 { if (this.dgvGrade.Rows[e.RowIndex].Cells[e.ColumnIndex].Value != DBNull.Value && Convert.ToInt32(this.dgvGrade.Rows[e.RowIndex].Cells[e.ColumnIndex].Value) < 60)//对不及格的成绩设置特殊样式 { this.dgvGrade.Rows[e.RowIndex].Cells[e.ColumnIndex].Style.ForeColor = Color.Red;//设置小于60的数字显示为红色 this.dgvGrade.Rows[e.RowIndex].Cells[e.ColumnIndex].Style.SelectionForeColor = Color.Red; this.dgvGrade.Rows[e.RowIndex].Cells[e.ColumnIndex].Style.Alignment = DataGridViewContentAlignment.MiddleRight; } } } //根据内容设置行标头 private void dgvDataTable_RowPostPaint(object sender, DataGridViewRowPostPaintEventArgs e) { if (this.dgvGrade.Rows[e.RowIndex].Cells["ColumnGrade"].Value == DBNull.Value) return; int intGrade = Convert.ToInt32(this.dgvGrade.Rows[e.RowIndex].Cells["ColumnGrade"].Value);//获取成绩 Image RowIcon;//标头图标 string strToolTip;//提示信息 if (intGrade >= 90) { RowIcon = TestDataGridViewRowStyle.Properties.Resources.GradeA;//从资源文件中获取图片 strToolTip = "Grade A"; } else if (intGrade >= 80) { RowIcon = TestDataGridViewRowStyle.Properties.Resources.GradeB; strToolTip = "Grade B"; } else if (intGrade >= 70) { RowIcon = TestDataGridViewRowStyle.Properties.Resources.GradeC; strToolTip = "Grade C"; } else if (intGrade >= 60) { RowIcon = TestDataGridViewRowStyle.Properties.Resources.GradeD; strToolTip = "Grade D"; } else { RowIcon = TestDataGridViewRowStyle.Properties.Resources.GradeF; strToolTip = "Grade F"; } e.Graphics.DrawImage(RowIcon, e.RowBounds.Left this.dgvGrade.RowHeadersWidth - 20, e.RowBounds.Top 4, 16, 16);//绘制图标 this.dgvGrade.Rows[e.RowIndex].HeaderCell.ToolTipText = strToolTip;//设置提示信息 } private void dgvGrade_CellPainting(object sender, DataGridViewCellPaintingEventArgs e) { if (e.RowIndex >=0 && e.ColumnIndex == 2) { if (this.dgvGrade.Rows[e.RowIndex].Cells["ColumnGrade"].Value == DBNull.Value) return; int intGrade = Convert.ToInt32(this.dgvGrade.Rows[e.RowIndex].Cells["ColumnGrade"].Value); Image img; if (intGrade >= 90) { img = TestDataGridViewRowStyle.Properties.Resources.high; } else if (intGrade >= 80) { img = TestDataGridViewRowStyle.Properties.Resources.arrow; } else if (intGrade >= 70) { img = TestDataGridViewRowStyle.Properties.Resources.up; } else if (intGrade >= 60) { img = TestDataGridViewRowStyle.Properties.Resources.down; } else { img = TestDataGridViewRowStyle.Properties.Resources.low; } Rectangle newRect = new Rectangle(e.CellBounds.X 3, e.CellBounds.Y 5, e.CellBounds.Height - 15, e.CellBounds.Height - 12); using (Brush gridBrush = new SolidBrush(this.dgvGrade.GridColor), backColorBrush = new SolidBrush(e.CellStyle.BackColor)) { using (Pen gridLinePen = new Pen(gridBrush, 2)) { // Erase the cell. e.Graphics.FillRectangle(backColorBrush, e.CellBounds); //划线 Point p1 = new Point(e.CellBounds.Left e.CellBounds.Width, e.CellBounds.Top); Point p2 = new Point(e.CellBounds.Left e.CellBounds.Width, e.CellBounds.Top e.CellBounds.Height); Point p3 = new Point(e.CellBounds.Left, e.CellBounds.Top e.CellBounds.Height); Point[] ps = new Point[] { p1, p2, p3 }; e.Graphics.DrawLines(gridLinePen, ps); //画图标 e.Graphics.DrawImage(img, newRect); //画字符串 e.Graphics.DrawString(intGrade.ToString(), e.CellStyle.Font, Brushes.Crimson, e.CellBounds.Left 20, e.CellBounds.Top 5, StringFormat.GenericDefault); e.Handled = true; } } } } }}
- 2014-08-29下载
- 积分：1
