go - bool 值设置为 true 无意中更改为 false

Question

在我的 golang 应用程序中，我根据表单输入将一些全局变量设置为 true，然后发现它们在后续函数中使用时已更改为 false。问题，在 golang 中声明和设置 bool 值的正确方法是什么？

var withKetchup bool
var withMustard bool

func orderProcess(w http.ResponseWriter, r *http.Request){

     r.ParseForm()
     withKetchup := r.FormValue("withKetchup")  //set to true (in form js form selection)
     withMustard := r.FormValue("withMustard")  //set to true

      code omitted ///
}

func prepareOrder(){

      code omitted//
     fmt.Println(withKetchup, withMustard) //both are false even though initially set to true
     if withKetchup == true && withMustard == true{

     }else {

     }


}

Answer 1

代码

 withKetchup := r.FormValue("withKetchup") 

使用 short variable declaration 声明并设置字符串类型的局部变量.要设置全局 bool 变量，请通过删除“:”将语句转换为赋值。此外，通过将表单值与 ""进行比较来计算 bool 值:

 withKetchup = r.FormValue("withKetchup") == "true"

因为服务器并发执行处理程序，所以使用这样的全局变量是不安全的。我建议将值作为参数传递给 prepareOrder:

func orderProcess(w http.ResponseWriter, r *http.Request){

     r.ParseForm()
     withKetchup := r.FormValue("withKetchup") == "true"
     withMustard := r.FormValue("withMustard") == "true"
     prepareOrder(withKetchup, withMustard)
}

func prepareOrder(withKetchup, withMustard bool){
     if withKetchup == true && withMustard == true{

     }else {

     }
}