JS can only input numbers and English, Chinese, all English code

English, Chinese, all English code
Below we provide a few common JS verification code, restrictions can only input numbers and English JS code restrictions can only input full-width characters English judgment function regular expression limit can only enter Chinese

Only numbers and English can be entered with regular expression restrictions: onkeyup= "Value=value.replace (/[w]/g,") "Onbeforepaste=" Clipboarddata.setdata (' text ', Clipboarddata.getdata (' text '). Replace (/[^d]/g, ') "restricts the use of regular expressions to only Chinese:

Onkeyup= "Value=value.replace (/[^u4e00-u9fa5]/g,") "Onbeforepaste=" Clipboarddata.setdata (' text ', Clipboarddata.getdata (' text '). Replace (/[^u4e00-u9fa5]/g, ') "restricts only full-width characters in regular expression:

Onkeyup= "Value=value.replace (/[^uff00-uffff]/g,") "Onbeforepaste=" Clipboarddata.setdata (' text ', Clipboarddata.getdata (' text '). Replace (/[^uff00-uffff]/g, ') "
/*
The English judgment function, returns True is all English, returns false to indicate not all is English
*/

function Isletter (str) {
if ("" ==str) {
return false;
}
for (var i=0;i var c = Str.charat (i);
if (c< "a" | | C> "Z") && (c< "a" | | C> "Z")) {
return false;
}
}
return true;
}