JavaScript 字串 數字 轉換
function wl(s){document.write((s||'')+'< br>\r\n');}
var s="1234.567";
var i=1234.567;
wl('string to int');
wl(parseInt(s));
wl(parseInt(s,10));//10進位
wl(parseInt(s,16));//16進位
wl(parseFloat(s));
wl(0+s);
wl(0+(+s));//+1234.567 正的1234.567，隱含轉換數字
wl('int to string');
wl(i.toString());
wl(i.toString(10));//10進位
wl(i.toString(16));//16進位
wl(i.toFixed(2));//四捨五入小數第二位，似乎沒有四捨六入五成雙的問題
寫個實用一點點的例子吧…色碼表：dob.tnc.edu.tw/demo.php
原程式：
document.write('<table border="0" width="100%" >');
var a,b,c,strA,strB,intF,intS;
function chgHex2(numeric) {
//chgHex2是副函數，負責更變0-15成為十六進制。而chgHex是主函數，負責把0-255轉成十六進制。
switch(numeric) {
case 0: strA='0'; break;
case 1: strA='1'; break;
case 2: strA='2'; break;
case 3: strA='3'; break;
case 4: strA='4'; break;
case 5: strA='5'; break;
case 6: strA='6'; break;
case 7: strA='7'; break;
case 8: strA='8'; break;
case 9: strA='9'; break;
case 10: strA='A'; break;
case 11: strA='B'; break;
case 12: strA='C'; break;
case 13: strA='D'; break;
case 14: strA='E'; break;
case 15: strA='F'; break;
}
return strA;
}
function chgHex(numeric) {
if(numeric<10) {
strB='0' + numeric;
} else if (numeric<16&&numeric>9) {
strB='0' + chgHex2(numeric);
} else {
intF=0; intS=0;
while (numeric>15) {
numeric=numeric-15;
numeric=numeric-1;
intF++;
}
intS=numeric;
strB=chgHex2(intF) + chgHex2(parseInt(intS));
}
return strB;
}
a=0; b=0; c=0;
var intTmp=-1;
document.write('<tr>');
for (a=0;a<=255;a=a+15){
for (b=0;b<=255;b=b+15) {
for (c=0;c<=255;c=c+60) {
intTmp++;
if (intTmp>10) {
document.write('</tr><tr>');
intTmp=0;
}
var strH=chgHex(a) + chgHex(b) + chgHex(c)
document.write('<td bgcolor="#'+ strH +'" style="font-family: Verdana; font-size: 10pt;">#' + strH + '</td>');
}
}
}
document.write('<td bgcolor="#FFFFFF" style="font-family: Verdana; font-size: 10pt;">#FFFFFF</td></tr></table>');修改一下：
document.write('<table border="0" width="100%" >');
var a,b,c,strA,strB,intF,intS;
function chgHex(numeric) {
var s=numeric.toString(16).toUpperCase();
return (s.length==1 ?'0'+s :s);
}
a=0; b=0; c=0;
var intTmp=-1;
document.write('<tr>');
for (a=0;a<=255;a=a+15){
for (b=0;b<=255;b=b+15) {
for (c=0;c<=255;c=c+60) {
intTmp++;
if (intTmp>10) {
document.write('</tr><tr>');
intTmp=0;
}
var strH=chgHex(a) + chgHex(b) + chgHex(c)
document.write('<td bgcolor="#'+ strH +'" style="font-family: Verdana; font-size: 10pt;">#' + strH + '</td>');
}
}
}
document.write('<td bgcolor="#FFFFFF" style="font-family: Verdana; font-size: 10pt;">#FFFFFF</td></tr></table>');