Chapter 3, T/F
A local variable cannot be accessed by code that appears inside the same method, but before the variable's declaration.
True
A variable of the decimal data type can hold real numbers with greater precision that the double data type.
True
An error occurs if a statement in one method tries to access a local variable declared inside another method.
True
An error occurs if you attempt to use a string that is set to null.
True
Any data the user enters into a TextBox control is stored in the control's Text property as a string, even if it is a number.
True
Because decimal is the preferred data type for storing monetary amounts, remembering that "m" stands for "money" might help you to remember that decimal literals must end with the letter M or m.
True
C# does not allow operations that mix the decimal and double data types unless you use a cast operator to explicitly convert one of the operands.
True
Each numeric format string can optionally be followed by an integer that indicates how many digits to display after the decimal point.
True
If a field is a variable of a numeric data type, it will be initialized to 0 by default if you do not explicitly initialize it with a value.
True
If all statements in a try block execute with no exception, the catch block is skipped.
True
If you need to store numbers and perform mathematical operations on them, you have to use a numeric data type.
True
In C#, a variable must be assigned a value before it can be used on the right side of an assignment statement.
True
In C#, the + operator has two uses: string concatenation and numeric addition.
True
In C#, you must declare a variable in a program before you can use it to store data.
True
It is usually best to break a long statement into multiple lines so you can read the code without scrolling the programming editor sideways.
True
Once you have assigned a value to a variable, you can use the variable in other operations.
True
Rounding can occur when the number of digits you have specified after the decimal point in the format string is smaller than the precision of the numeric value.
True
The C# language provides many data types for storing fundamental types of data, such as strings, integers, and real numbers.
True
The GroupBox control is found in the Toolbox window's Containers section.
True
The Math class provides two predefined named constants, Math.PI and Math.E, which are assigned mathematical values for pi and e.
True
The contents of a control's Text property is always a string.
True
The keyword const is a qualifier that tells the compiler to make the variable read-only.
True
The modulus operator (%) performs division between two integers, but rather than returning the quotient, it returns the remainder.
True
The purpose of a variable declaration is to tell the compiler you plan to use a variable of a specified name to store a particular type of data.
True
The same rules for identifiers that apply to control names also apply to variable names.
True
The using System; directive is required for any program that uses the Parse methods.
True
To get out of break mode in Visual Studio, click the Stop Debugging button on the standard toolbar or press Shift + F5 on the keyboard.
True
When you divide an integer by an integer in C#, the result is always an integer.
True
When you perform a math operation on two operands of the same data type, the result will always be of that data type.
True
When you store a data in a variable, the value replaces any data previously stored inside the variable.
True
When you write a catch clause, you can optionally assign a name to the exception object.
True
You assign an access key to a control through its Text property by placing an ampersand (&) before the letter you want to assign as an access key.
True
You can clear the contents of a TextBox control in the same way that you clear the contents of a Label control, by assigning an empty string to the control's Text property.
True
You cannot assign a decimal value to a double variable because the decimal data type allows for much great precision than the double data type.
True
You cannot assign a numeric value to a control's Text property because only strings can be assigned to the Text property.
True
GroupBox controls do not have their own TabIndex property.
False
If you don't write an access modifier in a field declaration, an error will occur.
False
If you want to display an ampersand character in the Text property of a control, use three ampersands in a row, such as (&&&).
False
In C#, a variable's data type is automatically determined by the type of value that is stored in the variable.
False
In C#, you use the & operator to concatenate strings.
False
Mathematical expressions involving multiple operators are always evaluated from left to right.
False
Only TextBox controls have a TabIndex property.
False
Primitive data types are not supported in the C# language.
False
Programs use data types to store data in memory.
False
Some operations can be performed on strings, but not on a control's Text property.
False
The C# compiler will compile code that attempts to use an unassigned variable.
False
The Parse methods work even if the string being converted contains an invalid numeric value.
False
Variables having the same name cannot be declared in different methods.
False
When a cast operator is applied to a variable, it changes the contents of a variable.
False
When a method ends, its local variables retain their values.
False
When you assign a double value to a decimal variable, the double value is implicitly converted to a decimal with no loss of data.
False
When you declare a named constant, an initialization value is not required.
False
You can assign integer constants to int, double, and decimal variables.
False
You can declare multiple variables of different data types in one program statement.
False
You can use a cast operator to convert a string to a numeric type.
False
After a variable has been declared, you can use the + operator to store a value in the variable.
False
Constant names must always be written in uppercase letters.
False
A constant field's value can only be changed by other statements inside the class.
False
A variable declaration specifies three things about a variable: its data type, name, and location in memory.
False
A variable is visible only to statements outside the variable's scope.
False
A variable of the int data type can hold numbers with a fractional part, such as 22.1 or −4.9.
False
A Panel control cannot display a title and does not have a Text property.
True
A Panel's border can be specified by its BorderStyle property.
True
A cast operator is the name of the desired data type, written inside parentheses and placed to the left of the value that you want to convert.
True
A double variable is stored in a format that programmers call double precision floating-point notation.
True
A field is visible to all methods within the same class.
True
A form's BackgroundImageLayout property is similar to the PictureBox control's SizeMode property.
True
A form's field values remain in memory as long as the form itself.
True
