# convertToHijriDate function Null safety

HijriDateTime convertToHijriDate(
1. DateTime date
)

Converts and retusn the hijri date for the given gregorian date.

## Implementation

``````HijriDateTime convertToHijriDate(DateTime date) {
int day = date.day;
int month = date.month;
int year = date.year;
int tMonth = month;
int tYear = year;
if (tMonth < 3) {
tYear -= 1;
tMonth += 12;
}
int yPrefix = (tYear / 100).floor();
int julianOffset = yPrefix - (yPrefix / 4.0).floor() - 2;
final int julianNumber = (365.25 * (tYear + 4716)).floor() +
(30.6001 * (tMonth + 1)).floor() +
day -
julianOffset -
1524;
yPrefix = ((julianNumber - 1867216.25) / 36524.25).floor();
julianOffset = yPrefix - (yPrefix / 4.0).floor() + 1;
final int b = julianNumber + julianOffset + 1524;
int c = ((b - 122.1) / 365.25).floor();
final int d = (365.25 * c).floor();
final int tempMonth = ((b - d) / 30.6001).floor();
day = (b - d) - (30.6001 * tempMonth).floor();
month = ((b - d) / 20.6001).floor();
if (month > 13) {
c += 1;
month -= 12;
}
month -= 1;
year = c - 4716;
final int modifiedJulianDate = julianNumber - 2400000;
// date calculation for year after 2077
const double iYear = 10631.0 / 30.0;
int z = julianNumber - 1948084;
final int cyc = (z / 10631.0).floor();
z = z - 10631 * cyc;
final int j = ((z - 0.1335) / iYear).floor();
final int iy = 30 * cyc + j;
z = z - (j * iYear + 0.1335).floor();
int im = ((z + 28.5001) / 29.5).floor();
/* istanbul ignore next */
if (im == 13) {
im = 12;
}

final int tempDay = z - (29.5001 * im - 29).floor();
int i = 0;
for (; i < _kDateCollection.length; i++) {
if (_kDateCollection[i] > modifiedJulianDate) {
break;
}
}
final int iln = i + 16260;
final int ii = ((iln - 1) / 12).floor();
int hYear = ii + 1;
int hMonth = iln - 12 * ii;
int hDate = modifiedJulianDate - _kDateCollection[i - 1] + 1;
if ((hDate.toString() + '').length > 2) {
hDate = tempDay;
hMonth = im;
hYear = iy;
}

return HijriDateTime(hYear, hMonth, hDate);
}``````