VB的浮点数处理

2024年6月15日发(作者：)

VB的浮点数处理

VB串口通信中经常会遇到10进制浮点数转为多字节Byte数据类型的情况，以及在接收后需转为10进制

浮点数需求。

VB有专门的API函数CopyMemory能处理2-10进制浮点数转换和10-2进制浮点数转换。

下列代码演示了10进制Single（单精度浮点型转为16进制字符显示的浮点数和其相反运算：

Option Explicit

Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any,

Source As Any, ByVal Length As Long)

Private Sub BinToSin_Click()

Dim sinStr As String

Dim sinSj As Single

Dim Buffer(3) As Byte

Dim i As Integer

sinStr = Text2

For i = 1 To Len(Text2) Step 2

Buffer((7 - i) / 2) = Val("&H" & Mid(sinStr, i, 2))

Next

CopyMemory ByVal VarPtr(sinSj), ByVal VarPtr(Buffer(0)), 4

Text3 = sinSj

End Sub

Private Sub SinToBin_Click()

Dim i As Integer

Dim hexData As String

Dim a As Single

Dim Buffer(3) As Byte

a = Val(Text1)

CopyMemory Buffer(0), a, 4

For i = 0 To 3

If Len(Hex(Buffer(i))) = 1 Then