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Flutter 如何编写扩展方法来检查空白dart_Flutter_Dart_Extension Methods - Fatal编程技术网

Flutter 如何编写扩展方法来检查空白dart

Flutter 如何编写扩展方法来检查空白dart,flutter,dart,extension-methods,Flutter,Dart,Extension Methods,谁能告诉我如何检查空白处吗 extension StringExtensions on String { bool isNullOrEmpty() => this == null || isEmpty; // check empty of white spaces } 谢谢使用包含方法,或者您可以使用regexp检查它,下面是一个示例 extension StringExtensions on String { bool get isNullOrEmpty {

谁能告诉我如何检查空白处吗

extension StringExtensions on String {

  bool isNullOrEmpty() => this == null || isEmpty;

 // check empty of white spaces


}

谢谢使用
包含
方法,或者您可以使用regexp检查它,下面是一个示例

extension StringExtensions on String {
  bool get isNullOrEmpty {
    bool _hasSpace = RegExp(r'\s').hasMatch(this);
    //  bool _hasSpace = this.contains(' ');

    return this == null || isEmpty || _hasSpace;
  }
}