简单，如果不工作去模板

Question

所以我正在做一个简单的 if 检查结构中的布尔值，但它似乎不起作用，它只是停止渲染 HTML。

所以下面的结构是这样的：

type Category struct {

    ImageURL      string

    Title         string

    Description   string

    isOrientRight bool

}

现在我有一个 Category 结构的切片，我可以用一个范围来显示它。

Bellow 是一个结构的示例：

juiceCategory := Category{

    ImageURL: "lemon.png",

    Title:    "Juices and Mixes",

    Description: `Explore our wide assortment of juices and mixes expected by

                        today's lemonade stand clientelle. Now featuring a full line of

                        organic juices that are guaranteed to be obtained from trees that

                        have never been treated with pesticides or artificial

                        fertilizers.`,

    isOrientRight: true,

}

我尝试了多种方法，如下所示，但都没有奏效：

{{range .Categories}}

    {{if .isOrientRight}}

       Hello

    {{end}}

    {{if eq .isOrientRight true}}

       Hello

    {{end}}

   <!-- Print nothing -->

   {{ printf .isOrientRight }} 

{{end}}

Answer 1

您必须导出要从模板访问的所有字段：将其第一个字母更改为大写I：type Category struct {&nbsp; &nbsp; ImageURL&nbsp; &nbsp; &nbsp; string&nbsp; &nbsp; Title&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;string&nbsp; &nbsp; Description&nbsp; &nbsp;string&nbsp; &nbsp; IsOrientRight bool}以及对它的每一个引用：{{range .Categories}}&nbsp; &nbsp; {{if .IsOrientRight}}&nbsp; &nbsp; &nbsp; &nbsp;Hello&nbsp; &nbsp; {{end}}&nbsp; &nbsp; {{if eq .IsOrientRight true}}&nbsp; &nbsp; &nbsp; &nbsp;Hello&nbsp; &nbsp; {{end}}&nbsp; &nbsp;<!-- Print nothing -->&nbsp; &nbsp;{{ printf .IsOrientRight }}&nbsp;{{end}}每个未导出的字段只能从声明包中访问。您的包声明了Category类型，text/template并且html/template是不同的包，因此如果您希望这些包可以访问它，则需要导出它。Template.Execute()返回一个错误，如果您已经存储/检查了它的返回值，您会立即发现这一点，因为您会收到与此类似的错误：模板：：2：9：在 <.isOrientRight> 处执行“”：isOrientRight 是结构类型 main.Category 的未导出字段在Go Playground上查看您的代码的工作示例。

Answer 2

如果生活对您施加了模板，由于某种原因具有小写变量名 - 可能是由 Pug 模板源构建的，也用于其他事情 - 有一种方法可以解决这个问题......您可以使用 amap[string]interface{}来保存要传递到模板中的值，因此在上面的示例中：juiceCategory := map[string]interface{}{&nbsp; &nbsp; "ImageURL": "lemon.png",&nbsp; &nbsp; "Title":&nbsp; &nbsp; "Juices and Mixes",&nbsp; &nbsp; "Description": `Explore our wide assortment of juices and mixes expected by&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; today's lemonade stand clientelle. Now featuring a full line of&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; organic juices that are guaranteed to be obtained from trees that&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; have never been treated with pesticides or artificial&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; fertilizers.`,&nbsp; &nbsp; "isOrientRight": true,}现在无需更改您的模板...