VB6 variables declared with the “As New” clause are known as auto-instancing variables.
CONVERT STRING TO DOUBLE VB6 CODE
VB Migration Partner automatically moves the variable declaration outside the code block: ' in VB.NET the x variable can be referenced only from by the code If Dim keyword appears inside an If, For, For Each, Do, While, or Select block, then VB2005 limits the scope of the variable to the block itself whereas VB6 makes the variable visible to the entire method: When the name of a VB6 member matches a VB.NET keyword it must be enclosed between square brackets, as in Examples are AddHandler, Handles, Shadows, and TimeSpan. Several VB.NET keywords aren’t reserved words under VB6 and can be used as member names. VB Migration Partner uses the CByte operator when converting to a Byte variable and CShort when converting to any other numeric data type. VB.NET requires that you use the appropriate conversion operator. VB6 supports implicit conversions from Boolan values to other numeric data types. VB.NET doesn’t support such implicit conversions and requires explicit calls to methods of the class:įor uniformity and readability’s sake, VB Migration Partner generates calls to ByteArrayToString6 and StringToByteArray6 methods when the original code implicitly converts a Byte array to a String, or vice versa. VB6 supports implicit conversions from String to Byte arrays, and vice versa, as in this code snippet:ĭim s1 As String, s2 As String, b() As Byte When converting a piece of VB6 to VB.NET such implicit conversions must become explicit by calls to the ToOADate and FromOADate methods of the Date type:įor uniformity and readability’s sake, VB Migration Partner generates calls to DateToDouble6 and DoubleToDate6 methods when the original VB6 code implicitly converts a Date value to Double, or vice versa.Ĭonversions between String and Byte arrays This is possible because a Date value is nothing but a Double value whose integer portion represents the number of days elapsed since Decemand whose fractional part represents the time portion of the date. VB6 allows you to use a Double variable whenever a Date value is expected, and vice versa. VB Migration Partner maps fixed-length strings to the VB6FixedString type, which mimics VB6 behavior more closely:ĭim buffer As VB6FixedString(256) Conversions between Date and Double types The assembly defines a FixedLengthString type which behaves like fixed-length strings, but there are significant differences with the original VB6 type. VB.NET doesn’t support fixed-length strings. VB6 fields, local variables, and members of Type structures can be defined as fixed-length strings, as in:Īn uninitialized fixed-length string initially contains only ASCII 0 characters when you assign any value to it, the value is truncated to the maximum length, or padded with spaces to the right if shorted than the maximum length.
However, it is recommended that you get rid of type declaration suffixes and convert them in standard and more readable As clauses. Now a variable whose name ends with “%” is a 32-bit integer a variable whose name ends with “&” is a 64-bit integer a variable whose name ends with is a Decimal variable. Type declaration suffixesĪ consequence of the fact that VB.NET redefines the meaning of Integer and Long keywords is that the meaning of type declaration suffixes has changed too.
NOTE: starting with version 1.52, the VB6Variant class is not officially supported. VB Migration Partner offers the option to render a Variant variable with the special VB6Variant type, if a SetType or ChangeType pragma is specified. NET variable can’t hold the special Empty, Null, and Missing values. In many cases, however, the two types aren’t equivalent.
VB.NET doesn’t support the Variant data type all Variant members are translated to Object members. For example, in VB6 a Currency operation might raise an overflow, but it would be evaluated correctly under VB.NET. However, the Decimal data type has greater precision and range than Currency, therefore you have no guarantee that math expressions deliver the same result they do in VB6. The Currency data type isn’t supported by VB.NET variables of this type should be converted to Decimal. (A VB.NET Long variable is a 64-bit signed integer.) A VB6 Integer variable is a 16-bit signed integer, therefore it should be translated to Short under VB.NET likewise, a VB6 Long variable is a 32-bit signed integer and should be translated to Integer under VB.NET.
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