验证字符串是否以 JavaScript 中的标点符号开头


假设我们有下列字符串。其中一个以问号开头,即标点符号 −

var sentence1 = 'My Name is John Smith.'
var sentence2 = '? My Name is John Smith.'

我们需要检查上述两个句子是否以标点符号开头。若要检查字符串是否以标点符号开头,代码如下 −

示例

var punctuationDetailsRegularExpression=/^[.,:!?]/
var sentence1 = 'My Name is John Smith.'
var output1 = !!sentence1.match(punctuationDetailsRegularExpression)
if(output1==true)
   console.log("This ("+sentence1+") starts with a punctuation");
else
   console.log("This ("+sentence1+") does not starts with a punctuation");
var sentence2 = '? My Name is John Smith.'
var output2 = !!sentence2.match(punctuationDetailsRegularExpression)
if(output2==true)
   console.log("This ( "+sentence2+") starts with a punctuation");
else
   console.log("This ( "+sentence2+" ) does not starts with apunctuation");

若要运行上述程序,您需要使用以下命令 −

node fileName.js.

此处我的文件名是 demo209.js。

输出

这将生成以下输出 −

PS C:\Users\Amit\javascript-code> node demo209.js
This (My Name is John Smith.) does not starts with a punctuation
This ( ? My Name is John Smith.) starts with a punctuation

更新于:01-Sep-2020

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