API Reference
A1
Utility helpers for parsing and converting Excel A1 references. Public so examples and consumers can reuse consistent logic without re-implementing regexes or math.
Inheritance
- Object
- A1
Methods
public static String ColumnIndexToLetters(Int32 index) #StringConverts a 1-based column index to Excel column letters (e.g., 1→"A", 27→"AA").
Parameters
- index System.Int32
- 1-based column index.
Returns
Excel column letters; returns "A" for non-positive inputs.
Examples
string col = A1.ColumnIndexToLetters(28); // "AB" int idx = A1.ColumnLettersToIndex("AB"); // 28
public static Int32 ColumnLettersToIndex(String letters) #Int32Converts column letters (e.g., "A", "AA") to a 1-based column index. Non-letter characters are ignored; returns 0 for empty/invalid input.
Parameters
- letters System.String
- Excel column letters.
Returns
1-based column index, or 0 when input yields no letters.
public static ValueTuple<Int32, Int32> ParseCellRef(String cellRef) #ValueTuple<Int32, Int32>Parses a single A1 cell reference (e.g., "B5") into a 1-based (row, column) tuple. Returns (0,0) when the input does not match a valid simple cell reference.
Parameters
- cellRef System.String
- A1 cell reference, without sheet prefix.
Returns
Tuple of row and column (1-based). Returns (0,0) if invalid.
public static ValueTuple<Int32, Int32, Int32, Int32> ParseRange(String a1Range) #ValueTuple<Int32, Int32, Int32, Int32>Parses an A1 range (e.g., "A1:B10") into 1-based, normalized bounds. If the bounds are inverted, they are swapped so that r1 <= r2 and c1 <= c2.
Parameters
- a1Range System.String
- A1 range string, without sheet prefix.
Returns
(r1, c1, r2, c2) 1-based coordinates.
Exceptions
ArgumentException– Thrown when the input is not a valid A1 range.
Examples
var (r1, c1, r2, c2) = A1.ParseRange("B2:D10"); // r1=2, c1=2, r2=10, c2=4
public static Boolean TryParseRange(String a1Range, out Int32 r1, out Int32 c1, out Int32 r2, out Int32 c2) #BooleanTries to parse an A1 range (e.g., "A1:B10") into 1-based, normalized bounds. Returns false when the input is not a valid A1 range.
Parameters
- a1Range System.String
- r1 System.Int32@
- c1 System.Int32@
- r2 System.Int32@
- c2 System.Int32@