Reading a String and Writing It To a File

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Creating this VCL application consists of the following steps:

1. Create a VCL Form with a button control.
2. Write the code to read the string and write it to a file.
3. Run the application.

To create a VCL Form

1. Create a directory in which to store your project files.
2. Choose File > New > Other > Delphi Projects or C++Builder Projects and double-click the VCL Forms Application icon. The VCL Forms Designer is displayed.
3. From the Standard page of the Tool palette, place a TButton component on the form.

To read and write a string

1. Select Button1 on the form.
2. In the Object Inspector, double-click the OnClick action on the Events tab.The Code Editor displays, with the cursor in the TForm1.Button1Click (Delphi) or TForm1::Button1Click (C++) event handler block.
3. For Delphi. place the cursor before the begin reserved word; then press return. This creates a new line above the code block.
4. Type the following variable declarations: TFileStream *fs const AnsiString str = "Hello";
5. Insert the cursor within the code block, and type the following code: fs = new TFileStream("temp.txt", fmCreate);

 fs->Write ((void*)str.c_str(), str.fmCreate);

To run the "Hello world" application

1. Save your project files; then choose Run > Run to build and run the application. The form displays with a button called Button1.
2. Click Button1.
3. Use a text editor to open the newly created file temp.txt, which is located in your project directory. The string 'Hello' displays in the file.

See Also

• VCL Overview
• Building a VCL Forms Application