javascript - Dojo lang.replace - 如何提供默认值，而不是“未定义”？

Question

Dojo用文本lang.replace()替换未定义的占位符。undefined是否可以在占位符中定义默认值？

假设我想要以下占位符：

<div class="message">The query returned {result.rows:0} rows</div>

占位符将替换为返回的行数，但当变量rows不可用时（例如，结果包含错误消息），它将替换为 0。

score 3 · Accepted Answer

There are two approaches you can consider. The first is to mixin the results object with defaults before passing it into the replace function.

var defaults = {
    rows: 0
};
var data = lang.mixin(lang.clone(defaults), result);

lang.replace(template, data);

The second approach is instead of passing a data object, pass a function that knows how to default the value when missing.

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