Exam 8: Text Files

In order to use the OpenFileDialog control, the programmer must first change its Name property to something other than the default OpenFileDialog1.

Each record of the file UN.txt contains four pieces of information (name, continent, population in millions, area) about one of the 192 member countries of the United Nations. The first two lines of the file are Afghanistan,Asia,28.2,251772 Albania,Europe,3.2,11100 What is the first line of the file created by the following code? Dim query = From line In IO.File.ReadAllLines("UN.txt") Let data = line.Split(","c) Let country = data(0) Let continent = data(1) Select country & " is in " & continent IO.File.WriteAllLines("NewFile.txt", query)

If the value of IO.File.Exists(filespec) is True, then the specified file exists.

Which one of the following is NOT an example of a bug?

If an existing text file is opened for output, the computer will append any new data to the end of this existing file.

Which exception will the following code generate? Dim num1 As Integer, num2 As Integer = 1000000 num1 = num2 * num2

Consider the following code. The Catch block of code will not be executed if the user enters which of the following when prompted? Private Sub btnCalc_Click(...) Handles btnCalc.Click Dim newNum, finalNum As Integer Dim message, message1 As String Try newNum = CInt(InputBox("How old are you?")) Catch message = "That answer is not an Integer value." MessageBox.Show(message) newNum = 0 Finally finalNum = newNum + 1 message1 = "Your age next year will be " & finalNum & "." MessageBox.Show(message1) End Try End Sub

The following statement could be used to set the Filter property of the OpenFileDialog control so that it displays files with the .txt extension.

When using Try-Catch-Finally blocks, the programmer is limited to three Catch blocks of code.

When a text file is created in Visual Basic using a StreamWriter, the extension .txt is automatically added to the file name if no other extension is specified.

What property is set to False in order to remove the row header column on the left side of a DataGridView control?

XML stands for

Which exception will the following code generate? Dim str As String str = "Visual Basic".Substring(14,2)

Each line of the file UN.txt contains four pieces of information (name, continent, population in millions, area) about one of the 192 member countries of the United Nations. The first two lines of the file are Afghanistan,Asia,28.2,251772 Albania,Europe,3.2,11100 What is the first line of the file created by the following code? Dim query = From line In IO.File.ReadAllLines("UN.txt") Let data = line.Split(","c) Let country = data(0) Let population = 1000000 * CDbl(data(2)) Select country & "," & population IO.File.WriteAllLines("NewFile.txt", query)

XML files must be loaded into XElement objects before being accessed with LINQ.

Which of the following terms is NOT used to refer to elements in an XML document?

In a Try-Catch-Finally block, the code in the first listed Catch block is executed if an exception is thrown in the Try block.

Select the example statement below that would open a text file for output.

What method is used to copy the contents of a string array or LINQ query into a text file?

The following statement could be used to set the Filter property of the OpenFileDialog control so that it displays files with the .txt extension.