“= + IF（...）”在Excel中做什么？(Does “=+IF(…)” do anything in Excel?)

 我为客户自动化一个大的Excel电子表格，并且我在他们的公式中不断遇到一个奇怪的结构。 几乎所有的IF函数都有这样的公式： 
 
=+IF(<cond1>,"text",IF(<cond2>,1,2))
 
 请注意等号后面紧跟的+号。 起初我认为这是虚假的，但它确实被广泛使用（数百个地方）。 然后，我想可能是强制结果被Excel解释为数字，但大多数使用它的地方都是IF函数，它们返回大多数结果值的非数字文本。 
 
 有谁知道这是否实际上在Excel公式中做了什么？ 
 
 （Excel 2007，如果这很重要） 

I am automating a large Excel spreadsheet for a customer and I keep coming across a strange construct in their formulas. Virtually all of their IF functions have formulas that look like this:
 
=+IF(<cond1>,"text",IF(<cond2>,1,2))
 
Note the + at the beginning, immediately after the equals sign. At first I thought it was spurious, but it sure is used extensively (hundreds of places). Then I thought that maybe it was to force the result to be interpreted as a numeric by Excel, but most of the places that use it are IF functions that return non-numeric text for the majority of their result values.
 
Does anyone know if this actually does anything in Excel formulas?
 
(Excel 2007, if that matters)

原文：https://stackoverflow.com/questions/15485499