if-statement - 多余的 'if'语句较少

Question

我的代码如下

 private fun validateInput(): Boolean {
     if (etReportRow1.text.toString() == "" 
         || etReportRow2.text.toString() == "" 
         || etReportRow3.text.toString() == "")
         return false
     else
         return true
 }

编译器告诉我

Redundant 'if' statement less... (Ctrl+F1) This inspection reports if statements which can be simplified to single statements. For example: if (foo()) { return true } else { return false } can be simplified to return foo().

建议的代码不会进入循环吗？

Answer 1

所有形式的陈述:

if(condition){
    return false
} else {
    return true
} 

可以简化为:

return !condition

因此，在您的情况下，它将导致:

return !(etReportRow1.text.toString() == "" || etReportRow2.text.toString() == "" || etReportRow3.text.toString() == "")

要么:

return 
    etReportRow1.text.toString().isNotEmpty() && 
    etReportRow2.text.toString().isNotEmpty() && 
    etReportRow3.text.toString().isNotEmpty()

注意: isNotEmpty()是扩展方法:

public inline fun CharSequence.isNotEmpty(): Boolean = length > 0

为了避免重复的代码，您还可以使用 Sequence:

public fun validateInput() = sequenceOf(etReportRow1, etReportRow2, etReportRow3)
    .map { it.text.toString() }
    .all { it.isNotEmpty() }