RtlMoveMemory to read an integer from a file

  • Thread starter Thread starter Bill Mittenzwey
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Bill Mittenzwey

I am trying to read a string of bytes out of a file and convert them into an
int. I can make it work in Visual Fox (see below), but I can't seem to get
the same code to work in c# (see below the fox sample).

Does anyone recognize this or can anyone let me know what I am doing wrong?
Is there a better way than the WinAPI?

in fox I can do this:

declare VOID RtlMoveMemory in win32api Double @Dest, Char @Src, Size_T
BytesToCopy

c = CHR(0) + CHR(0) + CHR(0) + CHR(0) + CHR(0) + CHR(0x80) + CHR(0x50)+
CHR(0x40)

VariableDecimals= 0
*This will round to 0 decimals.
set decimals to (VariableDecimals)
VariableValue = 10^(-VariableDecimals)
VariableLength = 8
=RtlMoveMemory(@VariableValue, @c, VariableLength )

The value of VariableValue will be 66


In c#:
At the top of the class:
[DllImport("kernel32.dll")]

public static extern void RtlMoveMemory(ref double dest, ref string src,
long bytesToCopy);

public static decimal convertNumber(string strValue, int varDec)

{

double varValue = Math.Pow(10,-1*varDec);

int varLen = 8;


RtlMoveMemory(ref varValue, ref strValue, varLen);

decimal outVal = Convert.ToDecimal(Math.Round(varValue,varDec));

return outVal;

}
 
You can also use a BinaryReader's ReadInt32 or ReadInt16 method if you need
to read an int. There are also ReadDouble and ReadDecimal methods.
 
Thanks to both posts. That really simplifies things.

Dmitriy Lapshin said:
You can also use a BinaryReader's ReadInt32 or ReadInt16 method if you need
to read an int. There are also ReadDouble and ReadDecimal methods.

--
Dmitriy Lapshin [C# / .NET MVP]
X-Unity Test Studio
http://www.x-unity.net/teststudio.aspx
Bring the power of unit testing to VS .NET IDE

Bill Mittenzwey gateway edi.com> said:
I am trying to read a string of bytes out of a file and convert them
Click to expand...
into
an
int. I can make it work in Visual Fox (see below), but I can't seem to get
the same code to work in c# (see below the fox sample).

Does anyone recognize this or can anyone let me know what I am doing wrong?
Is there a better way than the WinAPI?

in fox I can do this:

declare VOID RtlMoveMemory in win32api Double @Dest, Char @Src, Size_T
BytesToCopy

c = CHR(0) + CHR(0) + CHR(0) + CHR(0) + CHR(0) + CHR(0x80) + CHR(0x50)+
CHR(0x40)

VariableDecimals= 0
*This will round to 0 decimals.
set decimals to (VariableDecimals)
VariableValue = 10^(-VariableDecimals)
VariableLength = 8
=RtlMoveMemory(@VariableValue, @c, VariableLength )

The value of VariableValue will be 66


In c#:
At the top of the class:
[DllImport("kernel32.dll")]

public static extern void RtlMoveMemory(ref double dest, ref string src,
long bytesToCopy);

public static decimal convertNumber(string strValue, int varDec)

{

double varValue = Math.Pow(10,-1*varDec);

int varLen = 8;


RtlMoveMemory(ref varValue, ref strValue, varLen);

decimal outVal = Convert.ToDecimal(Math.Round(varValue,varDec));

return outVal;

}
Click to expand...
Click to expand...
 
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