public static bool WriteStringAttribute(hid_t hid, string key, string value, bool utf8 = true, bool variable = true)
{
if (H5A.exists(hid, key) == 0)
{
// Attribute doesn't exist.
return(variable ? CreateOrOverwriteVariableStringAttribute(hid, key, new string[] { value }, utf8)
: CreateOrOverwriteFixedStringAttribute(hid, key, value, utf8));
}
else
{
var attribute = H5A.open(hid, key);
if (attribute < 0)
{
return(false);
}
var type = H5A.get_type(attribute);
if (type < 0)
{
H5A.close(attribute);
return(false);
}
var typeClass = H5T.get_class(type);
if (typeClass == H5T.class_t.NO_CLASS)
{
H5T.close(type);
H5T.close(attribute);
return(false);
}
if (typeClass != H5T.class_t.STRING)
{
H5T.close(type);
H5T.close(attribute);
throw new ArgumentException("H5T.get_class(type) != H5T.class_t.STRING");
}
utf8 = H5T.get_cset(type) == H5T.cset_t.UTF8;
bool ok;
if (H5T.is_variable_str(type) > 0)
{
ok = CreateOrOverwriteVariableStringAttribute(hid, key, new string[] { value }, utf8);
}
else
{
ok = CreateOrOverwriteFixedStringAttribute(hid, key, value, utf8);
}
H5T.close(type);
H5T.close(attribute);
return(ok);
}
}
public static string ReadStringAttribute(hid_t hid, string key)
{
var attribute = H5A.open(hid, key);
if (attribute < 0)
{
throw new ArgumentException(string.Format("Attribute {0} not found.", key));
}
var type = H5A.get_type(attribute);
if (type < 0)
{
H5A.close(attribute);
throw new Exception("H5A.get_type failed.");
}
var typeClass = H5T.get_class(type);
if (typeClass != H5T.class_t.STRING)
{
H5T.close(type);
throw new Exception("Not a string attribute");
}
var utf8 = H5T.get_cset(type) == H5T.cset_t.UTF8;
var ascii = H5T.get_cset(type) == H5T.cset_t.ASCII;
if (!utf8 && !ascii)
{
H5T.close(type);
H5A.close(attribute);
throw new Exception("Neither ASCII nor UTF8.");
}
var isVariableString = H5T.is_variable_str(type);
if (isVariableString < 0)
{
H5T.close(type);
H5A.close(attribute);
throw new Exception("H5T.is_variable_str failed");
}
if (isVariableString > 0)
{
var space = H5A.get_space(attribute);
if (space < 0)
{
H5T.close(type);
H5A.close(attribute);
throw new Exception("H5A.get_space failed.");
}
hid_t count = H5S.get_simple_extent_npoints(space);
var rdata = new IntPtr[count];
H5A.read(attribute, type, new PinnedObject(rdata));
var attrStrings = new List <string>();
for (int i = 0; i < rdata.Length; ++i)
{
int attrLength = 0;
while (Marshal.ReadByte(rdata[i], attrLength) != 0)
{
++attrLength;
}
byte[] buffer = new byte[attrLength];
Marshal.Copy(rdata[i], buffer, 0, buffer.Length);
string part = utf8 ? Encoding.UTF8.GetString(buffer)
: Encoding.ASCII.GetString(buffer);
attrStrings.Add(part);
H5.free_memory(rdata[i]);
}
H5S.close(space);
H5T.close(type);
H5A.close(attribute);
return(attrStrings[0]);
}
// Must be a non-variable length string.
var size = H5T.get_size(type).ToInt32();
var unmanagedBuffer = new UnmanagedBuffer(size);
int result = H5A.read(attribute, type, unmanagedBuffer);
if (result < 0)
{
H5T.close(type);
H5D.close(attribute);
throw new IOException("Failed to read attribute.");
}
var bytes = new byte[size];
unmanagedBuffer.CopyTo(bytes, 0, bytes.Length);
H5T.close(type);
H5A.close(attribute);
var value = utf8 ? Encoding.UTF8.GetString(bytes)
: Encoding.ASCII.GetString(bytes);
return(value.TrimEnd('\0'));
}