In this tutorial, you will add a single control — a DataGrid control — that can display all the records from the dataset at the same time. An alternative would be to use individual controls such as text boxes to display one record at a time. That strategy then requires you to add navigation to the form. For simplicity, therefore, we will use a data grid.
The data grid must be bound to the dataset in order to display the data. To add a bound DataGrid control to the form surface 1. If you have not already done so, switch to the usercontrol designer view by clicking the tab at the top of the current window. Press F4 to display the Properties window. In the DataSource property, select DsCustomers1 as the data source. Do not choose DsCustomers1. In the DataMember property, select customers. Setting these two properties binds the customers data table in the DsCustomers1 dataset to the grid.
Resize the grid so you can see all the columns. Change its height so you will be able to see several customer records. Populating the DataGrid Control Although the data grid is bound to the dataset you created, the dataset itself is not automatically filled in.
Instead, you must fill the dataset yourself by calling a data adapter method. To populate the DataGrid control 1. From the Windows Forms tab of the Toolbox, drag a Button control onto the form. Name the button btnLoad and change the caption by setting its Text property to "Load". Double-click the button to create an event-handling method for its Click event.
In the method, clear the dataset you created, and then call the data adapter's Fill method, passing it the dataset you want to fill.
Clear ; sqlDataAdapter1. What this does is that every time users click the "Load" button, the DataSet is cleared and then reloaded from the server. Updating the Database When users make a change in the grid, the control automatically saves the updated record in the dataset. In Windows Forms, the data-binding architecture writes the values of data-bound controls to the data rows they are bound to.
However, when you work with a dataset, updates require two stages. After the data is in the dataset, you still have to send it from the dataset to the database. The data adapter can do this with its Update method, which examines every record in the specified data table in the dataset and, if a record has changed, sends the appropriate Update, Insert, or Delete command to the database automatically.
In this example, you will add a button to the form that users can press when they want to send their updates to the database. To update the database 1. Name the button btnUpdate and change the caption by setting its Text property to Save Changes in Database. In the method, call the data adapter's Update method, passing it the dataset containing the updates you want to send to the database.
Add a comment. Active Oldest Votes. Improve this answer. Bretto Bretto 11 1 1 bronze badge. That is true -- bit Internet Explorer may have problems loading the.
NET controls especially. NET 1. But on the machines that don't work we've tested with both bit and bit Internet Explorer, and both. NET 2. None of those cases worked. I believe these are all bit Windows 7 machines, though, if that makes a difference. Sign up or log in Sign up using Google. Sign up using Facebook.
Sign up using Email and Password. Net trust to a specific web server with the caspol. Net framework installed on the client machine that IE is using to load the control. Run the following command to establish.
The "Colorful Icon" Issue When attempting to load a Windows Forms control, the control does not appear; instead, a white box with a thin black outline appears in place of the control, with a colorful icon in the top-left corner.
TargetInvocationException: Exception has been thrown by the target of an invocation. VerificationException: Operation could destabilize the runtime. Net Framework trust to run, but trust has not been granted to the server hosting the control, or to the control itself, by the client machine the computer where Internet Explorer is running.
See "Setting up. Net framework trust" above. Other general things to check for a control failing to load with the "colorful icon" symptom: A: The client machine might be configured to not trust unsigned. Not sure about the exact setting. Adding the web server to "Trusted Sites" on the client will generally fix this.
This seems particularly common when the client is Windows Server. A: If the class constructor of the. Net control is throwing an uncaught exception, this behavior will occur. Try stepping through the constructor in a debugger assuming the control is one you are developing. A: Try clearing the Temporary Internet Files on the client machine especially if some.
Net components in the browser are working, but not others. A: If the same browser window was previously used to bring up the same.
Net control from a different virtual directory on the server machine, close the browser window and use a new one. A: There could be something invalid or malformed in the client machine's machine.
A: There could be an invalid or malformed iexplore. Try temporarily renaming the iexplore. More specific symptoms and resolutions for situations where IE is showing the "colorful icon" in place of the. A: Ensure that. Q: On the server machine, the most recent event in the IIS log is a error trying to load a config file linked from the web page where the. No Fusion Bind error is logged on the client.
A: Check the Windows filesystem permissions on the. Try giving the "Everyone" group full permissions on the file to establish whether or not this is the problem. If applying "Everyone" permissions does work to resolve the issue, you will probably then wish to remove "Everyone," and apply more fine-grained permissions, to allow IIS to serve the control, but without compromising security.
A: On the server, in IIS Manager, under File Security for the config file for that specific file, not the parent virtual directory security , if Anonymous access is checked, ensure that "Allow IIS to control password" is also checked.
Navigating in the browser directly to the config file referenced in the. Net control's web page results in a error even though the file really is there on the server. A: In the Internet Information Services Manager utility, open the Properties dialog for the config file's parent virtual directory. Q: A new. Net framework version was recently installed on the client, after which the control started failing to load.
A: Set up trust for the web server machine under the new. Net framework version as described above. The control may load properly from a different client machine, or when a different user is logged into the OS.
A: Clear the Shadow Cache for the user on the machine where the problem is occurring. Delete the entire directory tree under the "dl? Q: When using compressed. A: This may indicate some problem on the server or client with loading.
Net to load the controls from the cab file. In the example above, you would need to change "Typename" to "TypeName". A: Make sure that the DLL file referenced in the classid is present in the virtual directory. Try setting Execute Permissions to "Scripts only". A: When debugging an ASP. Use the real IIS server on the machine instead. You can debug the ASP. NET site has been initially opened in the browser. Net control, the control does not appear; instead, a white box with a thin black outline appears in place of the control, with an "X" icon in the top-left corner.
Thanks to both Eric and Aaron for helping me figure out this problem. It turned out that McAcfee site adviser add-on installed in IE was blocking access to. NET control. Although, it is curious that it would allow an ActiveX control on the form. It seems that McAfee does it own. NET related permission checking before the.
I disabled McAfee Site Advisor to fix the problem. One thing you may want to check, and this may be a shot in the dark, is your Temporary Internet Files on PC3. Make sure the assembly is actually being downloaded there. You may be over your limit if you have a lot of old files there. I'd clear out your Temporary Internet Files and try again. Also, check your Temporary Internet Files folder to see if it is actually there. If it's not being saved because of this, that would explain why fusion log isn't seeing anything.
Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. IE does not display a. Asked 12 years ago. Active 12 years ago.
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