Add toEightFigureString and toTenFigureString

Update to OSRef.php to add toEightFigureString and toTenFigureString. Allows for 10m and 1m accuracy grid references to be created from easting northing.

OSRef.php

@@ -87,14 +87,16 @@ public static function fromSixFigureReference($ref)
  }
 
  /**
- * Convert this grid reference into a string using a standard six-figure
- * grid reference including the two-character designation for the 100km
- * square. e.g. TG514131.
+ * Convert this grid reference into a grid reference string of a 
+ * given length (2, 4, 6, 8 or 10) including the two-character 
+ * designation for the 100km square. e.g. TG514131.
  * @return string
  */
- public function toSixFigureReference()
+ private function toGridReference($length)
  {
 
+ $halfLength = $length / 2;
+
  $easting = str_pad($this->x, 6, 0, STR_PAD_LEFT);
  $northing = str_pad($this->y, 6, 0, STR_PAD_LEFT);
 
@@ -112,7 +114,62 @@ public function toSixFigureReference()
  $minorLetterIndex = (int)(5 * $minorSquaresNorth + $minorSquaresEast);
  $minorLetter = substr(self::GRID_LETTERS, $minorLetterIndex, 1);
 
- return $majorLetter . $minorLetter . substr($easting, 1, 3) . substr($northing, 1, 3);
+ return $majorLetter . $minorLetter . substr($easting, 1, $halfLength) . substr($northing, 1, $halfLength);
+ }
+
+ /**
+ * Convert this grid reference into a string using a standard two-figure
+ * grid reference including the two-character designation for the 100km
+ * square. e.g. TG51 (10km square).
+ * @return string
+ */
+ public function toTwoFigureReference()
+ {
+ return $this->toGridReference(2);
+ }
+
+ /**
+ * Convert this grid reference into a string using a standard four-figure
+ * grid reference including the two-character designation for the 100km
+ * square. e.g. TG5113 (1km square).
+ * @return string
+ */
+ public function toFourFigureReference()
+ {
+ return $this->toGridReference(4);
+ }
+
+ /**
+ * Convert this grid reference into a string using a standard six-figure
+ * grid reference including the two-character designation for the 100km
+ * square. e.g. TG514131 (100m square).
+ * @return string
+ */
+ public function toSixFigureReference()
+ {
+ return $this->toGridReference(6);
+ }
+
+ /**
+ * Convert this grid reference into a string using a standard eight-figure
+ * grid reference including the two-character designation for the 100km
+ * square. e.g. TG51431312 (10m square).
+ * @return string
+ */
+ public function toEightFigureReference()
+ {
+ return $this->toGridReference(8);
+ }
+
+ /**
+ * Convert this grid reference into a string using a standard ten-figure
+ * grid reference including the two-character designation for the 100km
+ * square. e.g. TG5143113121 (1m square).
+ * @return string
+ */
+ public function toTenFigureReference()
+ {
+ return $this->toGridReference(10);
  }
 
  /**

tests/OSRefTest.php

@@ -36,6 +36,26 @@ public function testLatLngOSWorkedExample()
  self::assertEquals($expected, $LatLng->__toString());
  }
 
+ public function testToTwoFigureString()
+ {
+
+ $OSRef = new OSRef(530140, 184184);
+
+ $expected = 'TQ38';
+
+ self::assertEquals($expected, $OSRef->toTwoFigureReference());
+ }
+
+ public function testToFourFigureString()
+ {
+
+ $OSRef = new OSRef(530140, 184184);
+
+ $expected = 'TQ3084';
+
+ self::assertEquals($expected, $OSRef->toFourFigureReference());
+ }
+
  public function testToSixFigureString()
  {
 
@@ -66,6 +86,26 @@ public function testToSixFigureString3()
  self::assertEquals($expected, $OSRef->toSixFigureReference());
  }
 
+ public function testToEightFigureString()
+ {
+
+ $OSRef = new OSRef(216600, 771200);
+
+ $expected = 'NN16607120';
+
+ self::assertEquals($expected, $OSRef->toEightFigureReference());
+ }
+
+ public function testToTenFigureString()
+ {
+
+ $OSRef = new OSRef(216600, 771200);
+
+ $expected = 'NN1660071200';
+
+ self::assertEquals($expected, $OSRef->toTenFigureReference());
+ }
+
  public function testFromSixFigureString()
  {