code 128 c# free

c# code 128

barcode generator github c#, c# print 2d barcode, c# code 128 source, code 128 barcode generator c#, c# code 39, code 39 barcode generator c#, data matrix generator c# open source, c# data matrix barcode generator, gs1-128 c#, ean 13 check digit calculator c#, pdf417 source code c#, qr code in c# windows application, c# generate upc barcode

<asp:SqlDataSource ID="sourceEmployees" runat="server" ProviderName="System.Data.SqlClient" ConnectionString="<%$ ConnectionStrings:Northwind %>" SelectCommand="SELECT EmployeeID, FirstName, LastName, Title, City FROM Employees" UpdateCommand="UPDATE Employees SET FirstName=@FirstName, LastName=@LastName, Title=@Title, City=@City FROM Employees WHERE EmployeeID=@EmployeeID"> </asp:SqlDataSource> In this example, the parameter names aren t chosen arbitrarily. As long as you give each parameter the same name as the field it affects and preface it with the @ symbol (so FirstName because @FirstName), you don t need to define the parameter. That s because the ASP.NET data controls automatically submit a collection of parameters with the new values before triggering the update. Each parameter in the collection uses this naming convention. To try this, create a page with the SqlDataSource shown previously and a linked GridView control. Now, take the following steps to enable editing: 1. Select the GridView. In the smart tag, choose the Add New Column link. 2. In the Choose a Field Type box, select CommandField. Then, select the Edit/Update check box and the Show Cancel Button check box. Make sure all other check boxes are unchecked. 3. Click OK to add the column with editing controls. When you complete these steps, the GridView editing controls appear in an additional column. When you run the page and the GridView is bound and displayed, the edit column shows an Edit link next to every record. When clicked, this link switches the corresponding row into edit mode. All fields are changed to text boxes (with the exception of read-only fields), and the Edit link is replaced with an Update link and a Cancel link (see Figure 9-10).

NET assembly file (or a COM component) on your computer This is a good approach for testing custom components if you don t have the source project or you don t want to load it into Visual Studio where you might inadvertently modify it Figure 5-10 compares two ways to add a reference to the SherlockLib component by adding a reference to a currently loaded project and by adding a reference to the compiled DLL file..

A property from another control on the page. A value from the current query string. A value stored in the current user s session. A value from any cookie attached to the current request. A value from the current user s profile (see 24). A value posted to the page from an input control. Usually, you ll use a control property instead, but you might need to grab a value straight from the Forms collection if you ve disabled view state for the corresponding control.

Figure 9-10. Editing with the GridView The Cancel link returns the row to its initial state. The Update link passes the values to the SqlDataSource.UpdateParameters collection (using the field names) and then triggers the SqlDataSource.Update() method to apply the change to the database. Once again, you don t have to write any code. You can create similar parameterized commands for the DeleteCommand and InsertCommand. To enable deleting and inserting, you need to add a column to the GridView that has the ShowInsertButton and ShowDeleteButton properties set to true.

Once you add the reference, the corresponding DLL file will be automatically copied to the Bin directory of your current project. You can verify this by checking the Full Path property of the reference in the Properties window or just by browsing to the directory in Windows Explorer. The nice thing is that this file will automatically be overwritten with the most recent compiled version of the assembly every time you run the web application. It really is that easy. To use another component either from your own business tier, from a third-party developer, or from somewhere else all you need to do is add a reference to that assembly.

You don t need to remember the different tag names, as Visual Studio provides a handy editor that lets you create your command and define your parameters (see Figure 9-9). To see this dialog box, click the ellipsis (...) next to the SelectQuery property in the Properties window. When you type a command that uses one or more parameters, click the Refresh Parameters button, and the list of parameters will appear. You can then choose the mapping for each parameter by making a choice in the Parameter Source box.

The GridView is an extremely flexible control. Templates, one of its many features, allow you to define the controls and markup used when editing a record. This is handy if you want to enable editing through drop-down lists, add validation controls, or just fine-tune the appearance of a row in edit mode. You ll learn about templates in 10.