Delphi Programming Quiz grade 11

Which property of the TRichEdit component is used to align the paragraph?

• Paragraph.Alignment

• Paragraph.Tab[Index]

• Paragraph.TabCount

• Paragraph.Numbering

Answer explanation

The correct property to align paragraphs in the TRichEdit component is Paragraph.Alignment. This property directly controls the alignment of the text within the paragraph, making it the right choice among the options.

The Eof function returns True when the end of a file has been reached.

Answer explanation

The Eof function is designed to check if the end of a file has been reached during file operations. When it returns True, it indicates that there are no more data to read from the file.

How do you read lines of text from a TRichEdit component and store them in a variable?

• By using the Text property and assigning it to a string variable.

• By using the Paragraph.Alignment property and assigning it to a string variable.

• By using the Paragraph.TabCount property and assigning it to a string variable.

• By using the Lines property and assigning it to a string variable.

Answer explanation

The correct choice is to use the Lines property, which allows you to access each line of text in the TRichEdit component. Assigning it to a string variable enables you to store and manipulate the text easily.

The Reset function is used to open an existing file for reading.

Answer explanation

The Reset function is typically used to reset the file pointer to the beginning of an existing file, allowing it to be read from the start. Thus, it is indeed used for opening a file for reading.

Which function in Delphi is used to check if a file exists?

• FileCreate

• FileExists

• FileDelete

• FileRename

Answer explanation

The correct function to check if a file exists in Delphi is FileExists. This function returns a Boolean value indicating whether the specified file is present, making it the appropriate choice among the options provided.

Which function is used to close a text file in Delphi?

• ReadLn

• CloseFile

• Exit

• OpenFile

Answer explanation

In Delphi, the function used to close a text file is CloseFile. This function ensures that any changes made to the file are saved and that the file is properly closed, preventing data loss or corruption.

When reading from a text file in Delphi, it is recommended to use a CloseFile function to ensure that the file is always closed, even if an exception occurs during the reading process.

Answer explanation

Using CloseFile in Delphi ensures that the file is properly closed after reading, preventing resource leaks. This is crucial, especially when exceptions occur, as it guarantees that the file is closed regardless of errors.

What is the purpose of the Paragraph.TabCount property?

• To set the alignment of the paragraph.

• To set the number of tabs in a paragraph.

• To set the numbering style for a paragraph.

• To set the indentation of the paragraph.

Answer explanation

The Paragraph.TabCount property specifically indicates the number of tab stops set in a paragraph, making 'To set the number of tabs in a paragraph' the correct choice. The other options pertain to different paragraph formatting aspects.

What is the purpose of the try-and-except block in Delphi?

• To execute code only if an exception is raised.

• To execute code that does not raise exceptions.

• To terminate the program if an exception is raised.

• To execute code that may raise an exception, and handle the exception if it occurs.

Answer explanation

The try-and-except block in Delphi is used to execute code that may raise an exception and to handle that exception if it occurs, making it essential for robust error management.

You should always check if the end of the file has been reached before attempting to read from the file.

Answer explanation

Checking for the end of the file before reading prevents errors and ensures that you do not attempt to read beyond the available data, which can lead to exceptions or undefined behavior.