Takes a variable number of conditional statements

Description:

Traditional If / End If conditional block(s) to assist with flow control of a procedure.

These conditions in an If / End If block can take two forms:

1. If Field/Expression (Boolean)
2. If Field/Value Condition Field/Value/Expression (Condition)

When Boolean:

• Field/Expression is a boolean test such that if the Field/Expression is/returns empty it is False, and if it has any data it is True
• If an Expression is used, it must be surrounded with ( ) to be evaluated
• The Not operator can be placed in front of a boolean test to reverse the boolean logic. In the case of an Expression, Not must come before the ( ) eg. If Not ( )

When Condition:

• The list of Condition operators, Text and Math, are generic across other If commands in MOX, and are documented on the Syntax page. Note the separate list of Math vs. Text operators; the Math operators are doubled-up
• When testing a Field/Value against another Field/Value, ( ) must not be used
• Testing a Field/Value against an Expression, or an Expression against another Expression. Expressions on the left side of the Condition operator may not contain any of the symbols used by the list of Condition operators

And / Or / ElseIf / Else:

• The optional And statement will add additional criteria to a test. There may be as many And statements as needed
• The optional Or statement will add an alternative test. There may be as many Or statements as needed
• The And and Or statements can be thought of logically as (W And X) Or (Y And Z) -- It is not valid to organize as (W Or X) And (Y Or Z)
• Since And and Or are statements, they must be on their own logical lines of code. Use the : operator to start a new logical line of code on the same line of text
• The optional ElseIf statement specifies an additional test for when the If statement and any preceding ElseIf statements evaluated to False. There may be as many ElseIf statements as needed
• The optional Else statement may be included at the end of an If / End If block, and will execute when the If test and all/any ElseIf tests are False

Notes:

• As with all Expressions in MOX, an Expression in a test may include one or more MOX Functions. However, user-defined Functions cannot be used in an Expression; they are for assignments only
• The keyword Then may not be used at the end of these statements, since an If / Then pair is used on a single line with a single trailing command
• Nested If / End If blocks are not allowed, but inline If / Then tests are allowed within them, and Select / End Select blocks may be used inside an If / End If block and vice versa. This decision was made early on to prevent "spaghetti code", forcing developers to write more modular code by wrapping these nested levels in Methods, and it has worked well.

Examples:

If Req.Mode = "Post"
    abc = 123
    def = 456
End If

If Req.Mode = "Post" : And Req.HasFile
Or Req.Mode = "Get"  : And Not Req.HasFile
    abc = 123
ElseIf Not (SessionIsGroupType$ "DB Admin, Office Admin, Office")
    abc = 321
ElseIf 456 == (abc - def)
    HtmlAlert     "When testing Math, use the doubled-up Math operators"
    zxy = 456
ElseIf bOther
    def = 654
    If bFinal Then Other.Method.DoSomething
Else
    def = 456
End If

If (SessionIsGroupType$ "DB Admin, Office Admin, Office")
    HtmlAlert    "When evaluating an expression, surround it with ( )"
End If

If 65 >> 7
    HtmlAlert    "This is true because this is the numerical comparison operator"
End If

If 65 > 7
    HtmlAlert    "Does not display because this is the text comparison operator"
End If

[New]   True     = "y"
[New]   False    = ""

If True : HtmlAlert "This is true" : End If

If False
    HtmlAlert    "Does not display"
End If

If True : And True
    HtmlAlert    "This is true"
End If

If False : And False
    HtmlAlert    "Does not display"
End If

If True : And True : And False
    HtmlAlert    "Does not display"
End If

If True : Or True
    HtmlAlert    "This is true"
End If

If True : Or False
    HtmlAlert    "This is true"
End If

If True : And True
Or False
    HtmlAlert    "This is true"
End If

If True
Or False : And True
    HtmlAlert    "This is true"
End If

If True
Or False : And False
    HtmlAlert    "This is true"
End If

If False
Or False : And True
    HtmlAlert    "Does not display"
End If

If True : And False
Or True : And True
    HtmlAlert    "This is true"
End If

If False : Or False : Or False : Or True : Or False : Or False
    HtmlAlert    "This is true"
End If