Implementing IEditableObject when using as a datasource
If have used a class as datasource , you would know that to provide proper validation and you would nees to implement a IEditableObject, but if you sont its really simple all you have to do is provide 3 functions , The code Mentioned below is a simple example and I think you can take it from there
public class ReceiptPay : IEditableObject { public int FeeComponentId { get; set; } public string FeeComponent { get; set; } public decimal Amount { get; set; } private decimal amtbkp; private bool inTXN = false; public ReceiptPay(int FCId, string FC) { FeeComponentId = FCId; FeeComponent = FC; } #region IEditableObject Members public void BeginEdit() { if (!inTXN) { amtbkp = Amount; inTXN = true; } } public void CancelEdit() { if (inTXN) { Amount = amtbkp; inTXN = false; } } public void EndEdit() { inTXN = false; } #endregion }
Serialize and Deserialize object as XML
If you ever wanted to store an in memory obejct, i think serialization is the best possible method to do so, so is when you want to transport an object, i was using this for a long time now, now i have modified it a bit with generics
using System.Collections.Generic; using System.Text; using System.Xml; using System.IO; using System.Xml.Serialization; /// <summary> /// To convert a Byte Array of Unicode values (UTF-8 encoded) to a complete String. /// </summary> /// <param name="characters">Unicode Byte Array to be converted to String</param> /// <returns>String converted from Unicode Byte Array</returns> private static string UTF8ByteArrayToString(byte[] characters) { UTF8Encoding encoding = new UTF8Encoding(); string constructedString = encoding.GetString(characters); return (constructedString); } /// <summary> /// Converts the String to UTF8 Byte array and is used in De serialization /// </summary> /// <param name="pXmlString"></param> /// <returns></returns> private static Byte[] StringToUTF8ByteArray(string pXmlString) { UTF8Encoding encoding = new UTF8Encoding(); byte[] byteArray = encoding.GetBytes(pXmlString); return byteArray; } /// <summary> /// Serialize an object into an XML string /// </summary> /// <typeparam name="T"></typeparam> /// <param name="obj"></param> /// <returns></returns> public static string SerializeObject<t>(T obj) { try { string xmlString = null; MemoryStream memoryStream = new MemoryStream(); XmlSerializer xs = new XmlSerializer(typeof(T)); XmlTextWriter xmlTextWriter = new XmlTextWriter(memoryStream, Encoding.UTF8); xs.Serialize(xmlTextWriter, obj); memoryStream = (MemoryStream)xmlTextWriter.BaseStream; xmlString = UTF8ByteArrayToString(memoryStream.ToArray()); return xmlString; } catch { return string.Empty; } } /// <summary> /// Reconstruct an object from an XML string /// </summary> /// <param name="xml"></param> /// <returns></returns> public static T DeserializeObject</t><t>(string xml) { XmlSerializer xs = new XmlSerializer(typeof(T)); MemoryStream memoryStream = new MemoryStream(StringToUTF8ByteArray(xml)); XmlTextWriter xmlTextWriter = new XmlTextWriter(memoryStream, Encoding.UTF8); return (T)xs.Deserialize(memoryStream); } </t>
Vista Style Command link
Have you obeserved the new taskdialog in vista, (May I am the last one to write about this), but sure looks great, and it is easy to implement,
thre are lots of versions out there but like this the most, so here is the code
using System; using System.ComponentModel; using System.Drawing; using System.Drawing.Drawing2D; using System.Drawing.Imaging; using System.Windows.Forms; namespace CommandLink { [ToolboxBitmap(typeof(Button))] [DefaultEvent("Click")] public partial class CommandLink : Button { public CommandLink() { InitializeComponent(); this.DoubleBuffered = true; //Smooth redrawing this.ImageVerticalAlign = VerticalAlign.Middle; //Set Default } #region Fields--------------------------------- public enum State { Normal, Hover, Pushed, Disabled } public enum VerticalAlign { Top, Middle, Bottom } private State state = State.Normal; private int offset = 0; private string headerText = "Header Text"; private string descriptionText = "Description"; private Bitmap image; private Bitmap grayImage; private Size imageSize = new Size(24, 24); private VerticalAlign imageAlign = VerticalAlign.Top; private VerticalAlign textAlign = VerticalAlign.Middle; private Font descriptFont; #endregion #region Properties---------------------------- /// /// Gets or sets the string associated with the Header text of the control. /// [Category("Command Appearance"), Browsable(true), DefaultValue("Header Text")] public string HeaderText { get { return headerText; } set { headerText = value; this.Refresh(); } } /// /// Gets or sets the string associated with the Description text of the control. /// [Category("Command Appearance"), Browsable(true), DefaultValue("Description")] public string DescriptionText { get { return descriptionText; } set { descriptionText = value; this.Refresh(); } } /// /// Gets or sets the left-hand Bitmap object of the control. /// [Category("Command Appearance"), Browsable(true), DefaultValue(null)] public Bitmap Image { get { return image; } set { //Clean up if (image != null) image.Dispose(); if (grayImage != null) grayImage.Dispose(); image = value; if (image != null) grayImage = GetGrayscale(image); //generate image for disabled state else grayImage = null; this.Refresh(); } } /// /// Gets or sets the target size of the Image object. /// [Category("Command Appearance"), Browsable(true), DefaultValue(typeof(Size), "24,24")] public Size ImageScalingSize { get { return imageSize; } set { imageSize = value; this.Refresh(); } } /// /// Gets or sets the alignment of the Image object along the vertical axis. /// [Category("Command Appearance"), Browsable(true), DefaultValue(VerticalAlign.Top)] public VerticalAlign ImageVerticalAlign { get { return imageAlign; } set { imageAlign = value; this.Refresh(); } } /// /// Gets or sets the alignment of the displayed text along the vertical axis. /// [Category("Command Appearance"), Browsable(true), DefaultValue(VerticalAlign.Middle)] public VerticalAlign TextVerticalAlign { get { return textAlign; } set { textAlign = value; this.Refresh(); } } /// /// Gets or sets the Font object that will be applied to the header and description strings. /// [Category("Command Appearance")] public override Font Font { get { return base.Font; } set { base.Font = value; //Clean up if (descriptFont != null) descriptFont.Dispose(); //Update the description font, which is the same just 3 sizes smaller descriptFont = new Font(this.Font.FontFamily, this.Font.Size - 3); } } /// /// Gets a string representation of the header and description strings. /// [Browsable(false)] public override string Text { get { return this.HeaderText + ": " + this.DescriptionText; } } #endregion #region Events----------------------------------- protected override void OnPaint(PaintEventArgs e) { DrawBackground(e.Graphics); if (this.Focused && state == State.Normal) DrawHighlight(e.Graphics); switch (state) { case State.Normal: DrawNormalState(e.Graphics); break; case State.Hover: DrawHoverState(e.Graphics); break; case State.Pushed: DrawPushedState(e.Graphics); break; case State.Disabled: DrawNormalState(e.Graphics); //DrawForeground takes care of drawing the disabled state break; default: break; } } protected override void OnKeyPress(KeyPressEventArgs e) { if (e.KeyChar == Convert.ToChar(Keys.Enter)) this.PerformClick(); base.OnKeyPress(e); } protected override void OnGotFocus(EventArgs e) { this.Refresh(); base.OnGotFocus(e); } protected override void OnLostFocus(EventArgs e) { this.Refresh(); base.OnLostFocus(e); } protected override void OnMouseEnter(EventArgs e) { if (this.Enabled) state = State.Hover; this.Refresh(); base.OnMouseEnter(e); } protected override void OnMouseLeave(EventArgs e) { if (this.Enabled) state = State.Normal; this.Refresh(); base.OnMouseLeave(e); } protected override void OnMouseDown(MouseEventArgs e) { if (this.Enabled) state = State.Pushed; this.Refresh(); base.OnMouseDown(e); } protected override void OnMouseUp(MouseEventArgs e) { if (this.Enabled) { if (this.RectangleToScreen(this.ClientRectangle).Contains(Cursor.Position)) state = State.Hover; else state = State.Normal; } this.Refresh(); base.OnMouseUp(e); } protected override void OnEnabledChanged(EventArgs e) { if (this.Enabled) state = State.Normal; else state = State.Disabled; this.Refresh(); base.OnEnabledChanged(e); } protected override void Dispose(bool disposing) { if (disposing && components != null) { image.Dispose(); grayImage.Dispose(); descriptFont.Dispose(); components.Dispose(); } base.Dispose(disposing); } #endregion #region Drawing Methods------------------------- //Draws the light-blue rectangle around the button when it is focused (by Tab for example) private void DrawHighlight(Graphics g) { //The outline is drawn inside the button GraphicsPath innerRegion = RoundedRect(this.Width - 3, this.Height - 3, 3); //----Shift the inner region inwards Matrix translate = new Matrix(); translate.Translate(1, 1); innerRegion.Transform(translate); translate.Dispose(); //----- Pen inlinePen = new Pen(Color.FromArgb(192, 233, 243)); //Light-blue g.SmoothingMode = SmoothingMode.AntiAlias; g.DrawPath(inlinePen, innerRegion); //Clean-up inlinePen.Dispose(); innerRegion.Dispose(); } //Draws the button when the mouse is over it private void DrawHoverState(Graphics g) { GraphicsPath outerRegion = RoundedRect(this.Width - 1, this.Height - 1, 3); GraphicsPath innerRegion = RoundedRect(this.Width - 3, this.Height - 3, 2); //----Shift the inner region inwards Matrix translate = new Matrix(); translate.Translate(1, 1); innerRegion.Transform(translate); translate.Dispose(); //----- Rectangle backgroundRect = new Rectangle(1, 1, this.Width - 2, (int)(this.Height * 0.75f) - 2); Pen outlinePen = new Pen(Color.FromArgb(189, 189, 189)); //SystemColors.ControlDark Pen inlinePen = new Pen(Color.FromArgb(245, 255, 255, 255)); //Slightly transparent white //Gradient brush for the background, goes from white to transparent 75% of the way down LinearGradientBrush backBrush = new LinearGradientBrush(new Point(0, 0), new Point(0, backgroundRect.Height), Color.White, Color.Transparent); backBrush.WrapMode = WrapMode.TileFlipX; //keeps the gradient smooth incase of the glitch where there's an extra gradient line g.SmoothingMode = SmoothingMode.AntiAlias; g.FillRectangle(backBrush, backgroundRect); g.DrawPath(inlinePen, innerRegion); g.DrawPath(outlinePen, outerRegion); //Text/Image offset = 0; //Text/Image doesn't move DrawForeground(g); //Clean up outlinePen.Dispose(); inlinePen.Dispose(); outerRegion.Dispose(); innerRegion.Dispose(); } //Draws the button when it's clicked down private void DrawPushedState(Graphics g) { GraphicsPath outerRegion = RoundedRect(this.Width - 1, this.Height - 1, 3); GraphicsPath innerRegion = RoundedRect(this.Width - 3, this.Height - 3, 2); //----Shift the inner region inwards Matrix translate = new Matrix(); translate.Translate(1, 1); innerRegion.Transform(translate); translate.Dispose(); //----- Rectangle backgroundRect = new Rectangle(1, 1, this.Width - 3, this.Height - 3); Pen outlinePen = new Pen(Color.FromArgb(167, 167, 167)); //Outline is darker than normal Pen inlinePen = new Pen(Color.FromArgb(227, 227, 227)); //Darker white SolidBrush backBrush = new SolidBrush(Color.FromArgb(234, 234, 234)); //SystemColors.ControlLight g.SmoothingMode = SmoothingMode.AntiAlias; g.FillRectangle(backBrush, backgroundRect); g.DrawPath(inlinePen, innerRegion); g.DrawPath(outlinePen, outerRegion); //Text/Image offset = 1; //moves image inwards 1 pixel (x and y) to create the illusion that the button was pushed DrawForeground(g); //Clean up outlinePen.Dispose(); inlinePen.Dispose(); outerRegion.Dispose(); innerRegion.Dispose(); } //Draws the button in it's regular state private void DrawNormalState(Graphics g) { //Nothing needs to be drawn but the text and image //Text/Image offset = 0; //Text/Image doesn't move DrawForeground(g); } //Draws Text and Image private void DrawForeground(Graphics g) { //Make sure drawing is of good quality g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit; g.PixelOffsetMode = PixelOffsetMode.HighQuality; //Coordinates------------------------------- int imageLeft = 9; int imageTop = 0; int textLeft = 20; if (image != null) textLeft = imageLeft + imageSize.Width + 5; //adjust the text left coordinate to accomodate the image // //Text Layout------------------------------- string wrappedDescriptText = WordWrap(descriptionText, descriptFont, this.Width - (textLeft + offset) - 5); //Gets the width/height of the text once it's drawn out SizeF headerLayout = g.MeasureString(headerText, this.Font); SizeF descriptLayout = g.MeasureString(wrappedDescriptText, descriptFont); //Merge the two sizes into one big rectangle Rectangle totalRect = new Rectangle(0, 0, (int)Math.Max(headerLayout.Width, descriptLayout.Width), (int)(headerLayout.Height + descriptLayout.Height) - 4); //Align the text rectangle totalRect.X = textLeft; switch (textAlign) { case VerticalAlign.Top: totalRect.Y = 4; break; case VerticalAlign.Middle: totalRect.Y = (this.Height / 2) - (totalRect.Height / 2); break; case VerticalAlign.Bottom: totalRect.Y = this.Height - totalRect.Height; break; default: break; } //--------------------------------------------------- //Align the top of the image--------------------- if (image != null) { switch (imageAlign) { case VerticalAlign.Top: imageTop = 4; break; case VerticalAlign.Middle: imageTop = (imageSize.Height / 2); break; case VerticalAlign.Bottom: imageTop = this.Height - imageSize.Height; break; default: break; } } //----------------------------------------------- //Brushes-------------------------------- // Determine text color depending on whether the control is enabled or not Color textColor = this.ForeColor; if (!this.Enabled) textColor = SystemColors.GrayText; SolidBrush textBrush = new SolidBrush(textColor); //------------------------------------------ g.DrawString(headerText, this.Font, textBrush, totalRect.Left + offset, totalRect.Top + offset); g.DrawString(wrappedDescriptText, descriptFont, textBrush, totalRect.Left + 1 + offset, totalRect.Bottom - (int)descriptLayout.Height + offset); //Note: the + 1 in "totalRect.Left + 1 + offset" compensates for GDI+ inconsistency if (image != null) { if (this.Enabled) g.DrawImage(image, new Rectangle(imageLeft + offset, imageTop + offset, imageSize.Width, imageSize.Height)); else { //make sure there is a gray-image if (grayImage == null) grayImage = GetGrayscale(image); //generate grayscale now g.DrawImage(grayImage, new Rectangle(imageLeft + offset, imageTop + offset, imageSize.Width, imageSize.Height)); } } //Clean-up textBrush.Dispose(); } //Draws the solid background of the control private void DrawBackground(Graphics g) { SolidBrush backBrush = new SolidBrush(this.BackColor); g.FillRectangle(backBrush, this.DisplayRectangle); backBrush.Dispose(); } #endregion #region Helper Methods-------------------------- private static GraphicsPath RoundedRect(int width, int height, int radius) { RectangleF baseRect = new RectangleF(0, 0, width, height); float diameter = radius * 2.0f; SizeF sizeF = new SizeF(diameter, diameter); RectangleF arc = new RectangleF(baseRect.Location, sizeF); GraphicsPath path = new GraphicsPath(); // top left arc path.AddArc(arc, 180, 90); // top right arc arc.X = baseRect.Right - diameter; path.AddArc(arc, 270, 90); // bottom right arc arc.Y = baseRect.Bottom - diameter; path.AddArc(arc, 0, 90); // bottom left arc arc.X = baseRect.Left; path.AddArc(arc, 90, 90); path.CloseFigure(); return path; } private static Bitmap GetGrayscale(Image original) { //Set up the drawing surface Bitmap grayscale = new Bitmap(original.Width, original.Height); Graphics g = Graphics.FromImage(grayscale); //Grayscale Color Matrix ColorMatrix colorMatrix = new ColorMatrix(new float[][] { new float[] {0.3f, 0.3f, 0.3f, 0, 0}, new float[] {0.59f, 0.59f, 0.59f, 0, 0}, new float[] {0.11f, 0.11f, 0.11f, 0, 0}, new float[] {0, 0, 0, 1, 0}, new float[] {0, 0, 0, 0, 1} }); //Create attributes ImageAttributes att = new ImageAttributes(); att.SetColorMatrix(colorMatrix); //Draw the image with the new attributes g.DrawImage(original, new Rectangle(0, 0, original.Width, original.Height), 0, 0, original.Width, original.Height, GraphicsUnit.Pixel, att); //Clean up g.Dispose(); return grayscale; } private static string WordWrap(string originalString, Font font, int targetWidth) { string[] words = originalString.Split(' '); string wrappedString = words[0]; //Add one word at a time, making sure it doesn't go over for (int i = 1; i < words.Length; i++) { //Use TextRenderer since it has a static measure function if (TextRenderer.MeasureText(wrappedString + " " + words[i], font).Width <= targetWidth) wrappedString += " " + words[i]; //next word fits on the same line else wrappedString += Environment.NewLine + words[i]; //start it on the next line } return wrappedString; } public void PerformClick() { this.OnClick(null); } #endregion } }
I will also post for the complete task dialog in my next post.
* I did not write this code, credit to whomever who did this
How to make Linq distinct work for you
Have you even tried using linq on your objects then wanted to a distinct but couldn’t ?, Heres why this does not happen, .net doesn’t know how to distinguish between two custome objects (even though this looks obvious in most of the cases), So what should we do ?
You have to exted the IEqualityComparer with a custom extension which would allow you to compare your custom objects
Though mine is simple, I am sure that you will make more use of this than me
class Comparer : IEqualityComparer<GridDetails> { public bool Equals(GridDetails x, GridDetails y) { return x.Name == y.Name; } public int GetHashCode(GridDetails obj) { return obj.Name.GetHashCode(); } }
An Example usage would be :
this.grid.DataSource = data.ToList().Distinct(new Aptra.Profile.BO.Comparer());
Using a ASP.net Grid view using code
We have all used grid view along with data sources but some time you need to to that from code, the problem is most of us do not know how to use this from code, but Its not that difficult to that. Here’s a simple way to do that.
A Simple grid First column is a readonly templated field, second one a readonly bound field and third a templated entry field. At the Edit the edit command Field
<asp:GridView ID="GridView1" runat="server" CssSelectorClass="PrettyGridView" PageSize="50" AllowSorting="True" AutoGenerateColumns="False" EnableSortingAndPagingCallbacks="True"> <columns> <asp:templatefield HeaderText="Center Id" SortExpression="center_Id"> <edititemtemplate> <asp:Label ID="Label10" runat="server" Text='<%# Eval("bind1") %>'/> </edititemtemplate> <itemtemplate> <asp:Label ID="Label10" runat="server" Text='<%# Bind("bind1") %>'/> </itemtemplate> </asp:templatefield> <asp:boundfield DataField="City_Name" HeaderText="City Name" ReadOnly="True" SortExpression="City_Name"></asp:boundfield> <asp:templatefield HeaderText="Rate"> <edititemtemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("bind2") %>'/> </edititemtemplate> <itemtemplate> <asp:Label ID="Label1" runat="server" Text='<%# Bind("bind2") %>'/> </itemtemplate> </asp:templatefield> <asp:commandfield ShowEditButton="True"></asp:commandfield> </columns> </asp:GridView>
First Write a Function for loading data which will be reused on every action. I call it BindData()
Private Sub BindData() conn = New OleDbConnection(GetJetConnectionString) adap = New OleDbDataAdapter("Custom SQL Query", conn) Dim datatable1 As New DataTable adap.Fill(datatable1) dataset1 = New DataSet dataset1.Tables.Add(datatable1) Me.GridView1.DataSource = dataset1 Me.GridView1.DataBind() End Sub
Now since the gridview is binded from code we have to handle all its events. So When the user clicks on edit. Here I have done two things one is enable editing mode, then I store the data of textbox in a viewstate, so that it can be accessed later when updating, please remember that the regular method of e.OldValues and e.NewValues Will not work because we have to do that manually, (which can be done, but for our purposes we will use viewstate)
Protected Sub GridView1_RowEditing(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewEditEventArgs) Handles GridView1.RowEditing GridView1.EditIndex = e.NewEditIndex BindData() Dim row As GridViewRow = GridView1.Rows(GridView1.EditIndex) If row IsNot Nothing Then Dim t As TextBox = TryCast(row.FindControl("TextBox1"), TextBox) If t IsNot Nothing Then ViewState("OldRate") = t.Text End If End If End Sub
Now for the cancel part
Protected Sub GridView1_RowCancelingEdit(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewCancelEditEventArgs) Handles GridView1.RowCancelingEdit GridView1.EditIndex = -1 BindData() End Sub
Now for the update part. First new value is found out, if it is blank nothing is done, if old value does not Exist INSERT command is used if old value does exist UPDATE command is used. Here I did a Simple SQL execution but I think you will figure out a better way
Protected Sub GridView1_RowUpdating(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewUpdateEventArgs) Handles GridView1.RowUpdating Dim new_rate, old_rate As String old_rate = ViewState("OldRate") Dim row As GridViewRow = GridView1.Rows(e.RowIndex) If row IsNot Nothing Then Dim t As TextBox = TryCast(row.FindControl("TextBox1"), TextBox) If t IsNot Nothing Then new_rate = t.Text If new_rate = "" Then GridView1.EditIndex = -1 BindData() Exit Sub End If If new_rate = old_rate Then GridView1.EditIndex = -1 BindData() Exit Sub Else Dim label1 As Label = TryCast(row.FindControl("label10"), Label) Dim center_id As String = label1.Text Dim conn As New OleDbConnection(ConnectionString) Dim cmd As New OleDbCommand cmd.Connection = conn cmd.CommandType = CommandType.Text Dim SQL As String If old_rate = "" Then SQL = "INSERT INTO QUERY" Else SQL = "UPDATE QUERY" End If cmd.CommandText = SQL conn.Open() cmd.ExecuteNonQuery() conn.Close() GridView1.EditIndex = -1 BindData() End If Else GridView1.EditIndex = -1 BindData() End If End If End Sub