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如何检查文本字段在flift/dart中是否包含unicode字符?_Dart_Flutter - Fatal编程技术网

如何检查文本字段在flift/dart中是否包含unicode字符?

如何检查文本字段在flift/dart中是否包含unicode字符?,dart,flutter,Dart,Flutter,我正在尝试为消息传递应用程序计算TextField中的字符数。如果消息正文包含任何Unicode字符,则每条消息的总长度为70个字符,否则为160个。字符串。codeUnits是Unicode UTF-16代码单元的数组。 所以我想说可能是 int maxLengthOfTextField(String text){ final int maxBits = 128; List<int> unicodeSymbols = text.codeUnits.where((ch) =&

我正在尝试为消息传递应用程序计算
TextField
中的字符数。如果消息正文包含任何
Unicode
字符,则每条消息的总长度为70个字符,否则为160个。

字符串。codeUnits是Unicode UTF-16代码单元的数组。 所以我想说可能是

int maxLengthOfTextField(String text){
  final int maxBits = 128;
  List<int> unicodeSymbols = text.codeUnits.where((ch) => ch > maxBits ).toList();
  return unicodeSymbols.length > 0 ? 160 : 70;
}

final textFieldController = TextEditingController();
TextField(
  controller: textFieldController,
  maxLength: maxLengthOfTextField(textFieldController.text)
);
int-maxLengthOfTextField(字符串文本){
最终整数最大位数=128;
列出unicodeSymbols=text.codeUnits.where((ch)=>ch>maxBits.toList();
返回单键符号。长度>0?160:70;
}
final textFieldController=TextEditingController();
文本字段(
控制器:textFieldController,
maxLength:maxLengthOfTextField(textFieldController.text)
);

工作起来很有魅力。谢谢:)