如何在字母表中向上移動一個字符？

Question

我正在嘗試將 var 字母從A移動到B到C ...等等。 我知道這就是你在 java 中的做法，但你如何在 javascript 中做到這一點？

var letter = 'A';
letter++;


function drawOrganism() {
    var letter = "A"; //Initial Character
    var Organisms = 0;
    for (var col = 0; col <= organismArray.length - 1; col++) {
        for (var row = 0; row <= organismArray[col].length - 1; row++) {
            if (organismArray[col][row] == "*") {
                organismArray = howManyOrganisms(col, row, letter);
                letter++; // Moves up a Character
                Organisms++;
            }
        }
    }
    var printorganism = "";
    for (var i = 0; i <= 2; i++) {
        for (var j = 0; j <= 2; j++) {
            printorganism += organismArray[i][j];
        }
        printorganism += "<br>";
    }
    document.getElementById("drawOrganism1").innerHTML = printorganism;
}

Answer 1

這可能會有所幫助，您可以這樣做。

 let letter = 65; console.log(String.fromCharCode(letter)); // A console.log(String.fromCharCode(letter + 1)); // B

此外，如果您想像 Excel 樣式那樣遞增，您可以這樣做：

// 1 -> A, 2 -> B, 26 -> Z, 27 -> AA, 28 -> AB
toExcelXCoordinate(index: number): string {
    let coordinate = '';
    while (index > 0) {
      if (index % 26 === 0) {
        coordinate = 'Z' + coordinate;
        index = (index - 26) / 26;
      } else {
        coordinate = String.fromCharCode((index % 26) + 'A'.charCodeAt(0) - 1) + coordinate;
        index = (index - index % 26) / 26;
      }
    }

    return coordinate;
}

對於 Ascii 代碼，請查看 ASCII 表： http://www.asciitable.com/