Javascript 只保留字符串中的前 n 个字符？
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Keep only first n characters in a string?
提问by user978905
Is there a way in JavaScript to remove the end of a string?
JavaScript 中有没有办法删除字符串的结尾？
I need to only keep the first 8 characters of a string and remove the rest.
我只需要保留字符串的前 8 个字符并删除其余字符。
回答by Shad
You are looking for JavaScript's Stringmethod substring
您正在寻找 JavaScript 的String方法substring
e.g.
例如
'Hiya how are you'.substring(0,8);
Which returns the string starting at the first character and finishing before the 9th character - i.e. 'Hiya how'.
它返回从第一个字符开始到第 9 个字符之前结束的字符串 - 即“Hiya how”。
回答by KooiInc
You could use String.slice:
你可以使用String.slice：
var str = '12345678value';
var strshortened = str.slice(0,8);
alert(strshortened); //=> '12345678'
Using this, a String extension could be:
使用这个，字符串扩展可以是：
String.prototype.truncate = String.prototype.truncate ||
function (n){
return this.slice(0,n);
};
var str = '12345678value';
alert(str.truncate(8)); //=> '12345678'
回答by Wazy
Use substringfunction
Check this out http://jsfiddle.net/kuc5as83/
使用子字符串函数
检查这个http://jsfiddle.net/kuc5as83/
var string = "1234567890"
var substr=string.substr(-8);
document.write(substr);
Output >> 34567890
substr(-8)will keep last 8 chars
substr(-8)将保留最后 8 个字符
var substr=string.substr(8);
document.write(substr);
Output >> 90
substr(8)will keep last 2 chars
substr(8)将保留最后 2 个字符
var substr=string.substr(0, 8);
document.write(substr);
Output >> 12345678
substr(0, 8)will keep first 8 chars
substr(0, 8)将保留前 8 个字符
Check this out string.substr(start,length)
回答by Mike Christensen
You could try:
你可以试试：
myString.substring(0, 8);
回答by Sahil Muthoo
var myString = "Hello, how are you?";
myString.slice(0,8);
回答by pimvdb
You can use .substring, which returns a potion of a string:
您可以使用.substring，它返回一个字符串药水：
"abcdefghijklmnopq".substring(0, 8) === "abcdefgh"; // portion from index 0 to 8
