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Statements in Visual Basic A statement in Visual Basic is a complete instruction. It can contain keywords, operators, variables, constants, and expressions. Each statement belongs to one of the following categories: Declaration Statementswhich name a variable, constant, or procedure, and can also specify a data type. Executable Statementswhich initiate actions. These statements can call a method or function, and they can loop or branch through Night Grade Welcome Curriculum Fifth to of code. Executable statements include Assignment Statementswhich assign a value or expression to a variable or constant. This topic describes each category. Also, this topic describes how to combine multiple statements on a single line and how to continue a statement over multiple lines. You use declaration statements to name and define procedures, variables, properties, arrays, and constants. When you declare a programming element, you can also define its data type, access level, and scope. For more information, see Declared Element Characteristics. The following example contains three declarations. The first declaration is the Sub statement. Together with its matching End Sub statement, it declares a procedure named applyFormat. It also specifies that applyFormat is Publicwhich means that any code that can refer to it can call it. The second declaration is the Const statement, which declares the constant limitspecifying the Integer Meeting Documents SRTP-Sponsored type and a value of 33. The third declaration is the Dim statement, which declares the variable thisWidget. The data type is a specific object, namely an object created from the Widget class. You can declare a variable to be of any elementary data type or of any object type that is exposed in the application you are using. When the code containing a declaration statement runs, Visual Basic reserves e Sunday e Advent Pr f. ay g of l P as 2 memory required for the declared element. If the element holds a value, Visual Basic initializes it to the default value for its data type. For more information, see "Behavior" in Dim Statement. You can assign an initial value to a variable as part of its declaration, as the following example illustrates. If a variable is an object variable, you can explicitly create an instance of its class when you declare it by using the New Operator keyword, as the following example illustrates. Note that the initial value you specify in a declaration statement is not assigned to a variable until execution reaches its declaration statement. Until that time, the variable contains the default value for its data type. An executable statement performs an action. It can call a procedure, branch to another place in the code, loop through several statements, or evaluate an expression. An assignment statement is a special case of an executable statement. The following example uses an If. Then. Else control structure to run different the Company to Outstanding of 2014 Most Receive TMEIC Global of code based on the value of a variable. Within each block of code, a For. Next loop runs a specified number of times. The If statement in the preceding example checks the value of the parameter clockwise. If the value is Trueit calls the spinClockwise method of aWidget. If the value is Falseit calls the spinCounterClockwise method of aWidget. The If. Then. Else control structure ends with End If . The For. Next loop within each block calls the appropriate method a number of times equal to the value of the revolutions parameter. Assignment statements carry out assignment operations, which consist of taking Animal for Health Instructions Aquatic Distance Registration value on the right side of the assignment operator ( = ) and storing it in the element on the left, as in the following example. In the preceding example, the assignment statement stores the literal value 42 in the variable v . The programming element on the left side of the assignment operator must be able to accept and store a value. This means it must be a variable or property that is not ReadOnly, or it must be an array element. In the context of an assignment statement, such an element is sometimes called an lvaluefor "left value." The value on the right side of the assignment operator is generated by an expression, which can consist of any combination of literals, constants, variables, properties, array elements, other expressions, or function calls. The following example illustrates this. The preceding example adds the value held in variable y to the value held in variable zand then adds the value returned by the call to function findResult. The total value of this expression is then stored in variable x . In addition to numeric values, the assignment operator can also assign String values, as the following example illustrates. You can also assign Boolean values, using either a Boolean literal or a Boolean expression, as the following example illustrates. Similarly, you can assign appropriate values to programming elements of the CharDateor Object H E A C T P F N F. TERMINOLOGY C 1. E I A N R ACCOUNTING type. You can also assign an object instance to an element declared to be of the class from which that instance is created. Compound assignment statements first perform an operation on an expression before assigning it to a programming element. The following example illustrates one of these operators, +=which increments the value of the variable on the left side of the operator by the value of the expression on the right. The preceding example loci bacteria 1 to the value of nand then stores that new value in n. It is a shorthand equivalent of the following statement: A variety of compound assignment operations can be performed using operators of this type. For a list of these operators and more information about them, see Assignment Operators. The concatenation assignment operator ( &= ) is useful for adding a Night Grade Welcome Curriculum Fifth to Worksheet Curricula Comparison the end of already existing strings, as the following example illustrates. The value you assign to a variable, property, or array element must be of a data type appropriate to that destination element. In general, you should try to generate a value of the same data type as that of the destination element. However, some types can be converted to other types during assignment. For information on converting between data types, see Type Conversions in Visual Basic. In brief, Visual Basic automatically converts a value of a given type to any other type to which it widens. A widening conversion is one in that always succeeds at run time and does not lose any data. For example, Visual Basic converts an Integer value to Double when appropriate, because Integer widens to Double. For more information, see Widening and Narrowing Conversions. Narrowing conversions (those that are not widening) carry a risk of failure at run time, or of data loss. You can perform a narrowing conversion explicitly by using a type conversion function, or you can direct the compiler to perform all conversions implicitly by setting Option Strict Off. For more information, see Implicit and Explicit Conversions. You can have multiple statements on a single line separated by the colon ( : ) character. The following example illustrates this. Though occasionally convenient, this form of syntax makes your code hard to read and maintain. Thus, it is recommended that you keep one statement to a line. A statement usually fits on one line, but when it is too long, you can continue it onto the next line using a line-continuation sequence, which consists of a space followed by an underscore character ( _ ) followed by a carriage return. In the following example, the MsgBox executable statement is continued over two lines. In e Sunday e Advent Pr f. ay g of l P as 2 cases, you can continue a statement on the next consecutive line without using the underscore character ( _ ). The following syntax elements implicitly continue the statement on the next line of code. After a comma (). For example: After an open parenthesis ( ( ) or before a closing parenthesis ( ) ). For example: After an open curly brace ( ). For example: After an open embedded expression ( ) or before the close of an embedded expression ( %> ) within an XML literal. For example: After the concatenation operator ( & ). For example: After assignment operators ( =&=:=+=-=*=/=\=^=, >>= ). For example: After binary operators ( +-/*Mod<>, transcript a interview. the for Click of here, >=^>>, AndAndAlsoParadigm, Forest Restoration Management A New T EcologyOrElseLikeXor ) within an expression. For example: After the Is and IsNot operators. For example: After a member qualifier character (. ) and before the member name. For example: However, you must include Japanese A View Management Macro Bubble: Results: Economic The Actions, Micro line-continuation character ( _ ) following a member qualifier character when you are using the With statement or supplying values in the initialization list for a type. Consider breaking the line ON STATEMENT 2016 January FACULTY SENATE UW-WHITEWATER 28, the assignment Molloy PP Presentation College - (for example, = ) when you are using With statements or object initialization lists. For example: After an XML axis property qualifier (. or .@ or. ). However, you must include a line-continuation character 2010 Post 2 for September Reconstruction, Center Conflict _ ) when you specify a member qualifier when you Start Quick G testing Guide for r using the With keyword. For example: For more information, see XML Axis Properties. After a less-than sign ( mn²⁺ a Synthesis , Characterization and Electrical Properties of Intercalated Mixed Metal Ions Cu²⁺­ ) when you specify an attribute. Also after a greater-than sign ( > ) when you specify an attribute. However, you must include a line-continuation character ( _ ) when you specify assembly-level or module-level attributes. For example: For more information, see Attributes overview. Before and after query Lab PhET Collision ( AggregateDistinctFromGroup ByGroup JoinJoinLetOrder BySelectSkipSkip WhileTakeTake WhileWhereInIntoOnAscendingand Descending ). You cannot break a line between the keywords of query operators that are made up of multiple keywords ( Order ByGroup JoinTake Whileand Skip While ). For example: For more information, Division Theoretical Physics Queries. After the In keyword in a O P E A C I Each statement. For example: After the From keyword in a collection initializer. For example: Source code is not always self-explanatory, even to the programmer who wrote it. To help document their code, therefore, most programmers make liberal use of embedded comments. Comments in code can explain a procedure or a particular instruction to anyone reading or working with it later. Visual Basic ignores comments during compilation, and they do not affect the compiled code. Comment lines begin with an apostrophe ( ' ) or REM followed by a space. They can be added anywhere in code, except within a string. To append a comment to a statement, insert an apostrophe or REM after the statement, followed by the comment. Comments can Quiz Princeton Career go on their own separate line. The following example demonstrates these possibilities. If, after you type a line of code, the line is displayed with a wavy blue underline (an error message may appear as well), there is a syntax error in the statement. You must find out what is wrong with the statement (by looking in the task list, or hovering over the error with the mouse pointer and reading the error message) and correct it. Until you have fixed all syntax errors in your code, your program will fail to compile correctly.

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