tableadapter

There are two different data access methods: connection, command, and datareader for data operations, and dataadapter for data operations, data is generally stored in the data set dataset in the memory. In this way, you can operate on the data in the memory, and then pass the modification to the database at the appropriate time. 1. Create a dataset: 1. Right-click solution to add a new item and find the dataset in the data: 2. Add a connection to the data connection in the server resource m

" interface is not displayed, you can click the report design interface,"Data", "Report", and other options appear in the top menu.You can select "display data source" under the "data" menu ")9. Click "Add new data source". The "tableadapter Configuration Wizard" appears"10. Select data connection (for example, to connect to the local northwind database) and next11. Select whether to save the connection string to the application configuration file. Ne

Discontinued fields;3. Issue an update request to the data Access layer DAL through the TableAdapter update () method. For simplicity, this overloaded method omits an important business logic-checking and ensuring that a product that will be marked as discontinued is not the only product provided by its provider. You can add it, or do it better, and write this logic into a separate method. The following code is the new UpdateProduct overload method

(string productName, decimal unitprice, int productID) { Northwind.productsdatatable products = Adapter.getproductbyproductid (ProductID); if (products. Count = = 0) //No matching record found and return false to false; Northwind.productsrow product = products[0]; Product. ProductName = ProductName; if (UnitPrice = = null) product. Setunitpricenull (); else product. UnitPrice = Unitprice.value; Update the product record int rowsaffected = adapter.update (product);

, which we added in the data access layer, in the 61st chapter, "Encapsulation of database modifications in a transaction", is layer. In some cases, these batch data processing interfaces can greatly enhance the efficiency of end users. The review of processing batch data ends here. In the next series, we'll look at a variety of more advanced scenarios in the data access layer in layer. This includes the use of stored procedures in the TableAdapter m

Data controls support a variety of methods for handling null or missing data. For example, the GridView, FormView, and DetailsView both support the Emptydatatext or EmptyDataTemplate properties, which you can use to specify what the control displays when the data source does not return rows of data. We just need to set one of the Emptydatatext and EmptyDataTemplate (if all two are set, EmptyDataTemplate will be overloaded). You can also specify the ConvertEmptyStringToNull property on the bound

String name; Private String sex; private int age; Public person () { super (); } Public person (string name, string sex, int age) { super (); this.name = name; This.sex = sex; This.age = age; } Public String GetName () {return name; } public void SetName (String name) { this.name = name; } Public String Getsex () {return sex; } public void Setsex (String sex) { this.sex = sex; } public int getage (

configuration process is no longer tired, you can search in the Help "Manually Configuring Web Samples", follow the steps to configure IIS. Note that if you are using VS2005, you can run without configuration, as long as the file location option is set to file system when you create the WEB project. Also note that in the Web mode, you need to add the following paragraph in the Web.config file: Next time we'll show you how to load and display data on a report(ii)--binding data sources In the pre

Asp.net| Advanced | Data data controls support a variety of methods for handling null or missing data. For example, the GridView, FormView, and DetailsView both support the Emptydatatext or EmptyDataTemplate properties, which you can use to specify what the control displays when the data source does not return rows of data. We just need to set one of the Emptydatatext and EmptyDataTemplate (if all two are set, EmptyDataTemplate will be overloaded). You can also specify the ConvertEmptyStringToNu

Return to the "ASP.net 2.0 Data Tutorial directory" Introduction To end the previous sections, we've explored how to display data using the GridView, DetailsView, and FormView controls. These controls simply manipulate the data that is provided to it. Generally, these controls access data by using a data source control, such as ObjectDataSource. We've seen how ObjectDataSource plays an agent role between the ASP.net page and the potential data. When a GridView needs to display data, it calls t

save a lot of time. 6. Install a physical machine for load balancing ). Some Server OS also has such configuration functions. 7. program skills-ADO. NET If you can use DataReader, do not use DataSet/able. The former can read quickly without consuming memory. The latter is elastic, but slow, consumes a lot of memory for each user. If you use the default value-DataSet of the SqlDataSource control to connect to the data source of the DropDownList control, the performance will of course be affected

/southeast ">7 Extended application (empty line and label)The last line of the query results in a blank line, the following is the code to go blank lineDatagridview1.allowusertoaddrows = False Code for each line callout numberTry e.graphics.drawstring ((E.rowindex + 1). ToString (), E.inheritedrowstyle.font, New SolidBrush (color.cadetblue), e.rowbounds.location.x +, E. ROWBOUNDS.LOCATION.Y + 5) Catch

, including data source (database) access and commercial logic code, the site preparation and cutting should be completed with the View, so as to retain the system's Elasticity in future expansion or rewriting. This layer is like the custom class, DataSet (. xsd), TableAdapter ,... And so on. ◆ The Controller (Java Servlet) is used to control the "process" of the entire website processing and coordinates the process transfer and redirection between th

, 1,Null,-14 m, 10,Null,Null,False, 1 ); } Catch(ArgumentException AE) { Response. Write ("There was a problem :"+ AE. Message ); } We will see in the following tutorial that when you insert, modify, or delete operation data using a data Web Control, the exception thrown from BLL can be handled directly in an Event Handler without using try... Catch Block to wrap the code. Summary An application with a good architecture has a clear hierarchy, and each layer encapsulates a specific ro

After FormView is marked, the next step is to determine whether the value of UnitsInStock is less than or equal to 10. This is similar to that in DetailView. First, create a DataBound event. Figure: Create a DataBound event for processing Declare the DataItem attribute of FormView In the event to the ProductsRow instance, determine the value of UnitsInPrice, and display the corresponding value in red. protectedvoidLowStockedProductsInRed_DataBound(objectsender,EventArgse) { //G

GridView, all data is displayed. Compared with the previous three steps, step 2 is somewhat different. In step 2, The GridView lists all the data. A GridViewRow instance is created and bound to a record. Two events, GridViewRow, added to the GridView, are triggered: · RowCreated-triggered when GridViewRow is created · RowDataBound-triggered when the current record is bound to GridViewRow. For the GridView, use the following steps 1. DataBinding event triggered 2. Bind data to the data binding c

. We will discuss them in future articles. If none of the preceding four types (DataRow, Pager Rows Footer, Header) are suitable for the corresponding values, an empty data item is returned, therefore, we need to check the RowType attribute of GridViewRow in the code to determine: protectedvoidHighlightCheapProducts_RowDataBound(objectsender,GridViewRowEventArgse) { //MakesureweareworkingwithaDataRow if(e.Row.RowType==DataControlRowType.DataRow) { //GettheProdu

dataset is a class generated by Visual Studio Based on the Data Warehouse schema. The type of its members is determined by this schema. A strongly typed dataset itself is composed of dataset, able, and child classes of the datarow class inherited from ADO. net. In addition to the strongly typed able, the strongly Typed Dataset now also includes the tableadapter class, which contains various methods for filling the datatable in the dataset and returni

means you can let it inherit from any object you want. All the classes created by using the LINQ to SQL designer are defined as "partial Classification", which means you can have in-depth code of your choice, add some additional attributes, methods, and events to them. Different from the dataset/tableadapter method provided in vs2005, when using the LINQ to SQL designer, you do not need to provide SQL query statements when defining your data model an

Let's take a look at the end of this article: This article uses two controls, "updatepanel" and "updateprogress", to present the animation effect of the data during the update and provide a friendly interface for users to wait. It's cool! This document also describes how to create a dataset. When I study it, I can't say it? The detailed steps are as follows: 1. Open "Visual Studio 2005", "create a website", select "Atlas web site" under "My templates", and click OK. 2. Prepare the following tw