You can use the single-line syntax for a single condition with code to execute if it's true. The Select.Case Statement might be more useful when you evaluate a single expression that has several possible values. Else block must end with an End If statement. The ElseIf, Else, and End If statements can be preceded only by a line label. In the multiline syntax, the If statement must be the only statement on the first line.

Else statements can be nested within each other. Else statement, but no ElseIf clause can appear after an Else clause. You can have as many ElseIf clauses as you want in an If. The ElseIf and Else clauses are both optional. After executing the statements following Then, ElseIf, or Else, execution continues with the statement following End If. If no elseifcondition evaluates to True, or if there are no ElseIf statements, the statements following Else are executed. When a True elseifcondition is found, the statements immediately following the associated ElseIf are executed. If condition is False, each ElseIf statement (if there are any) is evaluated in order. If condition is True, the statements following Then are executed. Else statement is encountered, condition is tested. One or more statements that are executed if no previous condition or elseifcondition expression evaluates to True. Then that are executed if elseifcondition evaluates to True. Must evaluate to True or False, or to a data type that is implicitly convertible to Boolean.

Then that are executed if condition evaluates to True. Required in the single-line syntax optional in the multiline syntax. If the expression is a Nullable Boolean variable that evaluates to Nothing, the condition is treated as if the expression is False, and the ElseIf blocks are evaluated if they exist, or the Else block is executed if it exists.

This article includes several examples that illustrate uses of the If. Conditionally executes a group of statements, depending on the value of an expression.

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