HOW TO OPEN ANOTHER FILE WITH THE BUTTON IN C

First of all, you need to determine whether the file in the location you specified exists.

if (file path)).

file path);

The file doesn't exist! ", "Tips",What kind of file is the file?,If the system has software to open it by default, press what it says.。

File name of the file";

string path1 = @"d:\";Open the file on drive D;

string path2 = @"d:\test";Call Explorer and open the test folder on drive D.

explorer",path2);

Write as above in the button click event, and remember to modify the path of the file or folder.

Open the file and folder with the process class file, and directly call the path folder of the file province with this command.

Folder path"

For example, open the d: folder.

It's explorer d:

**A whole bunch of them on the web Just copy it.

The essence of the question is how to start a new process with C**:

Here's an example of a simple starting a new process

startinfo = new application path string);

entrance parameters; checkprocess = ;

Handoff? Is it the focus or?

If it is in the same form, define a form variable, for example: int temp;

Set temp = 10 in the first button click;

In the second button click, you can use it like this: int myvalue = temp; myvalue will be equal to 10.

Your SQL statement was written incorrectly.

sqlcommand cmd = new sqlcommand("update book set ISBN='3' where bookid='"+"'", con)；;

Write it like this or.

sqlcommand cmd = new sqlcommand("update book set ISBN='3' where bookid=''",, con)；;

That's how you can write it.

There are three ways for you to choose:

1.Stored in the session.

2.Stored in viewstate.

3.Put a hiddenfiled widget on the interface and store the value there.

Use global variables or static variables, such as if you defined static string str="";You have str= in the first click event"ddd";

Then you can use string str1=str in the second click;

Save this data with a session, or put this data in a widget on the page, such as a hidden widget.

Find a place to store the packets.

Instantiate one!! Use in this category!!

form1 jumps duform2 and closes self-form1.

dao**: version.

button in the matter.

void btn_click(object sender, eventargs e)

The form is equivalent to a class, and the parameters between classes are OK.

This question is a bit nonsense.,After you directly get a global class encapsulation.,You can call it in **.,Why do you want to get it into button1? Delegates and events should be fine.

Define a global variable str=;

Refresh str in the change event of button, and call str in button2;

I don't know if the LZ requirements are met.

private void methodname().

Directly in the onclick event of button2.

Write a separate function and call it.