Question

我想将变色变为蓝色。蓝色到红色。和红色到绿色。你能帮我吗？感谢...

def age
  return 'No Date of Birth' unless date_of_birth.present?

  days_alive = Date.now - date_of_birth
  years = (days_alive / 365).to_i
  months = ((days_alive % 365) / 30).to_i
  [pluralized(years, 'year'), pluralized(months, 'month')].compact.join(' ')
end

def pluralized(quantity, noun)
  return nil if quantity.zero?
  return noun.singularize if quantity == 1
  noun.pluralize
end

Answer 1

您的代码中存在许多语法错误。请考虑以下修订：

function ColorChange() {
    var color = "green";
    if(color == "green"){
        color = "blue";
    }
    else if(color == "blue"){
        color = "red";
    }
    else{
        color = "green";
    }
}

此外，如果您手动设置var color = "green";，那么如果您的if阻止，则

如果您在根据其值调用此函数时尝试更改全局变量，则可能如下所示：

true

如果您希望此函数采用var color = "green"; ... function ColorChange() { if(color == "green"){ color = "blue"; } else if(color == "blue"){ color = "red"; } else{ color = "green"; } }颜色并返回置换结果，请考虑以下内容：

string

总的来说，您可能不熟悉JavaScript，可能需要考虑beginner tutorial to get familiar with the syntax

Answer 2

function ColorChange(color) {
    if (color == "green") {
        color = "blue";
    }
    else if (color == "blue") {
       color = "red";
    }
    else {
       color = "green";
    }
return color;

}

我想在js中改变var color。怎么了？

2 个答案: