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Javascript 如何从变量中删除所有非数字字符_Javascript - Fatal编程技术网

Javascript 如何从变量中删除所有非数字字符

Javascript 如何从变量中删除所有非数字字符,javascript,Javascript,如何从javascript变量中删除所有文本字符(不是数字或浮点) function deduct(){ var getamt= document.getElementById('cf').value; //eg: "Amount is 1000" var value1 = 100; var getamt2 = (value1-getamt); document.getElementById('rf').value=getamt2; } 我想要getamt作为号

如何从javascript变量中删除所有文本字符(不是数字或浮点)

function deduct(){
    var getamt= document.getElementById('cf').value; //eg: "Amount is 1000"
    var value1 = 100;
    var getamt2 = (value1-getamt);
    document.getElementById('rf').value=getamt2;
}

我想要
getamt
作为号码
parseInt
正在给出
NaN
结果。

使用如下正则表达式:

var getamt= document.getElementById('cf').value; //eg: Amount is 1000
var value1 = 100;
var getamt2 = value1 - getamt.replace( /\D+/g, ''); // this replaces all non-number characters in the string with nothing.
console.log(getamt2);

您可以替换非数字

var str=“金额为1000”;
var num=+str.replace(/[^0-9.]/g,”);

console.log(num)
var getamt2=(value1-Number(getamt))
@epascarello
例如:“Amount is 1000”
可能的重复项--请参阅第二个答案
getamt.replace(/[^\d.-]/g',)
注意,您需要在重复项上看到一个不可接受的答案来处理floats。这只会从字符串的开头而不是中间或结尾删除非数值