还有另一种解决方案。如果您将颜色存储为普通的十六进制字符串，并且不想为其添加不透明度(前导“FF”):

将十六进制字符串转换为int 要将十六进制字符串转换为整数，请执行以下操作之一: var myInt = int。解析(hexString，基数:16); 或 var myInt = int.parse("0x$hexString"); 作为0x(或-0x)的前缀将使int。将默认值解析为基数16。 通过代码添加不透明度到你的颜色 Color = new Color(myInt).withOpacity(1.0);

“# b74093”?好吧……

到HEX配方

int getColorHexFromStr(String colorStr)
{
  colorStr = "FF" + colorStr;
  colorStr = colorStr.replaceAll("#", "");
  int val = 0;
  int len = colorStr.length;
  for (int i = 0; i < len; i++) {
    int hexDigit = colorStr.codeUnitAt(i);
    if (hexDigit >= 48 && hexDigit <= 57) {
      val += (hexDigit - 48) * (1 << (4 * (len - 1 - i)));
    } else if (hexDigit >= 65 && hexDigit <= 70) {
      // A..F
      val += (hexDigit - 55) * (1 << (4 * (len - 1 - i)));
    } else if (hexDigit >= 97 && hexDigit <= 102) {
      // a..f
      val += (hexDigit - 87) * (1 << (4 * (len - 1 - i)));
    } else {
      throw new FormatException("An error occurred when converting a color");
    }
  }
  return val;
}

简单的扩展基于@Serdar回答https://stackoverflow.com/a/57943307/4899849

extension HexString on String {
  int getHexValue() => int.parse(replaceAll('#', '0xff'));
}

用法:

'#b74093'.getHexValue()

要将十六进制字符串转换为整数，请执行以下操作:

int hexToInt(String hex)
{
  int val = 0;
  int len = hex.length;
  for (int i = 0; i < len; i++) {
    int hexDigit = hex.codeUnitAt(i);
    if (hexDigit >= 48 && hexDigit <= 57) {
      val += (hexDigit - 48) * (1 << (4 * (len - 1 - i)));
    } else if (hexDigit >= 65 && hexDigit <= 70) {
      // A..F
      val += (hexDigit - 55) * (1 << (4 * (len - 1 - i)));
    } else if (hexDigit >= 97 && hexDigit <= 102) {
      // a..f
      val += (hexDigit - 87) * (1 << (4 * (len - 1 - i)));
    } else {
      throw new FormatException("Invalid hexadecimal value");
    }
  }
  return val;
}

电话的例子:

Color color = new Color(hexToInt("FFB74093"));

你可以写一个小的控制台工具来转换字符串:

import 'dart:convert';
import 'dart:io';

void main() {
  while (true) {
    var line = stdin.readLineSync(encoding: utf8);

    print(HexColor.fromHex(line!));
  }
}

class HexColor {
  static fromHex(String hexString) {
    final buffer = StringBuffer();
    if (hexString.length == 6 || hexString.length == 7) buffer.write('ff');
    buffer.write(hexString.replaceFirst('#', ''));
    return int.parse(buffer.toString(), radix: 16);
  }
}

在文件中添加此函数

Color parseColor(String color) {
  String hex = color.replaceAll("#", "");
  if (hex.isEmpty) hex = "ffffff";
  if (hex.length == 3) {
    hex = '${hex.substring(0, 1)}${hex.substring(0, 1)}${hex.substring(1, 2)}${hex.substring(1, 2)}${hex.substring(2, 3)}${hex.substring(2, 3)}';
  }
  Color col = Color(int.parse(hex, radix: 16)).withOpacity(1.0);
  return col;
}

然后像-一样使用它

Container(
    color: parseColor("#b74093")
)