public bool TryFormat(Span <char> destination, int fieldCount, out int charsWritten)
{
if (fieldCount == 0)
{
charsWritten = 0;
return(true);
}
else if (fieldCount == 1)
{
return(_Major.TryFormat(destination, out charsWritten));
}
StringBuilder sb = ToCachedStringBuilder(fieldCount);
if (sb.Length <= destination.Length)
{
sb.CopyTo(0, destination, sb.Length);
StringBuilderCache.Release(sb);
charsWritten = sb.Length;
return(true);
}
StringBuilderCache.Release(sb);
charsWritten = 0;
return(false);
}
private static string ExpandEnvironmentVariablesCore(string name)
{
int currentSize = 100;
StringBuilder result = StringBuilderCache.Acquire(currentSize); // A somewhat reasonable default size
result.Length = 0;
int size = Interop.Kernel32.ExpandEnvironmentStringsW(name, result, currentSize);
if (size == 0)
{
StringBuilderCache.Release(result);
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
}
while (size > currentSize)
{
currentSize = size;
result.Capacity = currentSize;
result.Length = 0;
size = Interop.Kernel32.ExpandEnvironmentStringsW(name, result, currentSize);
if (size == 0)
{
StringBuilderCache.Release(result);
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
}
}
return(StringBuilderCache.GetStringAndRelease(result));
}
private static string GetEnvironmentVariableCore(string variable)
{
if (AppDomain.IsAppXModel() && !AppDomain.IsAppXDesignMode())
{
// Environment variable accessors are not approved modern API.
// Behave as if the variable was not found in this case.
return(null);
}
StringBuilder sb = StringBuilderCache.Acquire(128); // A somewhat reasonable default size
int requiredSize = Win32Native.GetEnvironmentVariable(variable, sb, sb.Capacity);
if (requiredSize == 0 && Marshal.GetLastWin32Error() == Win32Native.ERROR_ENVVAR_NOT_FOUND)
{
StringBuilderCache.Release(sb);
return(null);
}
while (requiredSize > sb.Capacity)
{
sb.Capacity = requiredSize;
sb.Length = 0;
requiredSize = Win32Native.GetEnvironmentVariable(variable, sb, sb.Capacity);
}
return(StringBuilderCache.GetStringAndRelease(sb));
}
private static string GetEnvironmentVariableCore(string variable)
{
StringBuilder sb = StringBuilderCache.Acquire(128); // A somewhat reasonable default size
int requiredSize = Win32Native.GetEnvironmentVariable(variable, sb, sb.Capacity);
if (requiredSize == 0 && Marshal.GetLastWin32Error() == Win32Native.ERROR_ENVVAR_NOT_FOUND)
{
StringBuilderCache.Release(sb);
return(null);
}
while (requiredSize > sb.Capacity)
{
sb.Capacity = requiredSize;
sb.Length = 0;
requiredSize = Win32Native.GetEnvironmentVariable(variable, sb, sb.Capacity);
}
return(StringBuilderCache.GetStringAndRelease(sb));
}
public bool TryFormat(Span <char> destination, int fieldCount, out int charsWritten)
{
if (fieldCount == 0)
{
charsWritten = 0;
return(true);
}
// TODO https://github.com/dotnet/corefx/issues/22403: fieldCount==1 can just use int.TryFormat
StringBuilder sb = ToCachedStringBuilder(fieldCount);
if (sb.Length <= destination.Length)
{
sb.CopyTo(0, destination, sb.Length);
StringBuilderCache.Release(sb);
charsWritten = sb.Length;
return(true);
}
StringBuilderCache.Release(sb);
charsWritten = 0;
return(false);
}
/// <summary>
/// Helper function for retrieving a localized string resource via MUI.
/// The function expects a string in the form: "@resource.dll, -123"
///
/// "resource.dll" is a language-neutral portable executable (LNPE) file in
/// the %windir%\system32 directory. The OS is queried to find the best-fit
/// localized resource file for this LNPE (ex: %windir%\system32\en-us\resource.dll.mui).
/// If a localized resource file exists, we LoadString resource ID "123" and
/// return it to our caller.
/// </summary>
private static string TryGetLocalizedNameByMuiNativeResource(string resource)
{
if (string.IsNullOrEmpty(resource))
{
return(string.Empty);
}
// parse "@tzres.dll, -100"
//
// filePath = "C:\Windows\System32\tzres.dll"
// resourceId = -100
//
string[] resources = resource.Split(',');
if (resources.Length != 2)
{
return(string.Empty);
}
string filePath;
int resourceId;
// get the path to Windows\System32
string system32 = Environment.SystemDirectory;
// trim the string "@tzres.dll" => "tzres.dll"
string tzresDll = resources[0].TrimStart('@');
try
{
filePath = Path.Combine(system32, tzresDll);
}
catch (ArgumentException)
{
// there were probably illegal characters in the path
return(string.Empty);
}
if (!int.TryParse(resources[1], NumberStyles.Integer, CultureInfo.InvariantCulture, out resourceId))
{
return(string.Empty);
}
resourceId = -resourceId;
try
{
StringBuilder fileMuiPath = StringBuilderCache.Acquire(Path.MaxPath);
fileMuiPath.Length = Path.MaxPath;
int fileMuiPathLength = Path.MaxPath;
int languageLength = 0;
long enumerator = 0;
bool succeeded = UnsafeNativeMethods.GetFileMUIPath(
Win32Native.MUI_PREFERRED_UI_LANGUAGES,
filePath, null /* language */, ref languageLength,
fileMuiPath, ref fileMuiPathLength, ref enumerator);
if (!succeeded)
{
StringBuilderCache.Release(fileMuiPath);
return(string.Empty);
}
return(TryGetLocalizedNameByNativeResource(StringBuilderCache.GetStringAndRelease(fileMuiPath), resourceId));
}
catch (EntryPointNotFoundException)
{
return(string.Empty);
}
}
private static string InternalFlagsFormat(RuntimeType eT, TypeValuesAndNames entry, ulong result)
{
Debug.Assert(eT != null);
string[] names = entry.Names;
ulong[] values = entry.Values;
Debug.Assert(names.Length == values.Length);
int index = values.Length - 1;
StringBuilder sb = StringBuilderCache.Acquire();
bool firstTime = true;
ulong saveResult = result;
// We will not optimize this code further to keep it maintainable. There are some boundary checks that can be applied
// to minimize the comparsions required. This code works the same for the best/worst case. In general the number of
// items in an enum are sufficiently small and not worth the optimization.
while (index >= 0)
{
if ((index == 0) && (values[index] == 0))
{
break;
}
if ((result & values[index]) == values[index])
{
result -= values[index];
if (!firstTime)
{
sb.Insert(0, enumSeparatorString);
}
sb.Insert(0, names[index]);
firstTime = false;
}
index--;
}
string returnString;
if (result != 0)
{
// We were unable to represent this number as a bitwise or of valid flags
returnString = null; // return null so the caller knows to .ToString() the input
}
else if (saveResult == 0)
{
// For the cases when we have zero
if (values.Length > 0 && values[0] == 0)
{
returnString = names[0]; // Zero was one of the enum values.
}
else
{
returnString = "0";
}
}
else
{
returnString = sb.ToString(); // Return the string representation
}
StringBuilderCache.Release(sb);
return(returnString);
}
