C What is the control that needs to be saved as a file, and how to use it?

openfiledialog open = new openfiledialog();Create an open dialog box.

true;Set whether to automatically add extensions to files.

true;Check the files.

File (****)|****|All files (*.)";Set the type to open to *** and any file.

string a="";

if ( == If the user clicks OK

openfiledialog。

To use it: create an object of the OpenFileDialog class. In **, the showdialog method can be used to open the selection file dialog, and the full path of the selection can be obtained by returning whether it is worth pressing the "Open" button or the "Cancel" button, and the filename property.

If you want to filter the selected file types, just set the filter property.

For example, get the contents of the selected txt file:

openfiledialog dlgopenfile = new openfiledialog ;

if( ok means "open" is pressed;

Pull a button from the left, double-click the button to increase the click event, and write :

openfiledialog ofd = new openfiledialog();

openfiledialog open = new openfiledialog();Create an open dialog box.

true;Set whether to automatically add extension = true in files; Check the files.

File (****)|****|All files (*.)";Set the type to open to *** and any file.

string a="";

if ( == If the user clicks OK

Create an image object. Give it the image of the picturebox. Save it again.

Here's an example for you.

Front desk Two textboxes, three buttons

**int c = 0;

private void button1_click_1(object sender, eventargs e)

elseprivate void button2_click(object sender, eventargs e)

private void button3_click(object sender, eventargs e)

You try it, after button1 clicks, add the values of textbox1 and textbox2, and after getting it, click the corresponding button

The pop-up box is displayed.

I don't quite understand what the operator means by judging for himself. If he judges it himself, then the two buttons directly yes, on just click it himself.

Tell us what you're trying to achieve.

Find something similar.

It is better to judge the values of and above, otherwise an error will be reported.

Just put the dll in the same folder as your exe. Nothing else needs to be changed. Including ** aspects.

Explanation: For example, if you use this external dll in d: and then change the computer. The new computer's D: It's definitely gone.

The program will continue to look for d: below. Definitely can't find it. The program will then look for the default path. The default path is the path where the exe is located. Refer to it as soon as you find it. If you can't find it here, it's an error.

Put the dll directly into the program directory to facilitate compilation and running on other computers.

Just put the corresponding dll in the past.

1.New Item - User Control.

2.Drag the desired C control onto the user control and lay out 3Write the user control backend (for the C control dragged up before the operation)4Compile.

5.This user control can then be dragged where you want to use it, just like a C control.