问至少x个数字字符的javascript正则表达式

EN

/^(\D*\d){10}/

var valid = /^(\D*\d){10}/.test(str);

console.log(/^(\D*\d){10}/.test('123-456-7890 ext 41')); // true
console.log(/^(\D*\d){10}/.test('123-456-789')); // false

^ assert position at start of the string
1st Capturing group (\D*\d){10}
Quantifier: Exactly 10 times
Note: A repeated capturing group will only capture the last iteration.
Put a capturing group around the repeated group to capture all iterations or use a 
non-capturing group instead if you're not interested in the data
\D* match any character that's not a digit [^0-9]
Quantifier: Between zero and unlimited times, as many times as possible
\d match a digit [0-9]

var valid = input.replace(/[^\d]/g, '').length >= 10

(\d\D*){10}