/// <summary>
/// READ keyword
/// Read a string from the device into a substring of the specified fixed string.
/// </summary>
/// <param name="readManager">A ReadManager instance to use</param>
/// <param name="iostat">A reference variable that will be set to the I/O status</param>
/// <param name="start">The 1-based start index of the target string</param>
/// <param name="end">The 1-based end index of the target string</param>
/// <param name="fixedstrVar">The fixed string identifier to read into</param>
/// <returns>A zero value if the operation succeeds, or -1 if the operation fails</returns>
public static int READ(ReadManager readManager, ref int iostat, int start, int end, ref FixedString fixedstrVar)
{
if (readManager == null) {
throw new ArgumentNullException("readManager");
}
if (fixedstrVar == null) {
throw new ArgumentNullException("fixedstrVar");
}
if (end == -1) {
end = fixedstrVar.Length;
}
FixedString fixedString = new FixedString((end - start) + 1);
int charsRead = readManager.ReadString(ref fixedString);
if (charsRead == -1) {
iostat = IOError.ReadError;
} else {
fixedstrVar.Set(fixedString, start - 1, end - 1);
}
return charsRead;
}
// Read a string, formatted from the file.
int ReadStringFormatted(ref FixedString fixedstrVar)
{
int fieldWidth = 0;
int charsRead = 0;
int strSize = fixedstrVar.Length;
// Handle a repeat count first
if (_valueRepeatCount > 0) {
if (_hasValueRepeat) {
fixedstrVar = _valueRepeat.ToString();
}
--_valueRepeatCount;
return _valueCharCount;
}
// For input formats, only the field width is used and it
// determines the fixed number of characters to read.
FormatRecord record = Record();
if (record != null) {
fieldWidth = record.FieldWidth;
}
if (fieldWidth > 0) {
string realString = ReadChars(fieldWidth);
int index = Math.Max(0, realString.Length - strSize);
int length = Math.Min(strSize, realString.Length);
fixedstrVar.Set(realString.Substring(index));
charsRead = length;
} else {
StringBuilder str = new StringBuilder();
char ch = ReadNonSpaceChar();
if (ch == '\'' && record == null) {
ch = ReadChar();
while (ch != EOF && ch != EOL) {
if (ch == '\'') {
ch = ReadChar();
if (ch != '\'') {
break;
}
}
str.Append(ch);
++charsRead;
ch = ReadChar();
}
SkipSeparators(ch);
} else {
while (charsRead < strSize && ch != EOL && ch != EOF) {
str.Append(ch);
ch = ReadChar();
++charsRead;
}
BackChar();
}
fixedstrVar.Set(str.ToString());
}
return charsRead;
}
