<script type=
"text/javascript"
>
function
substr(str, len)
{
if
(!str || !len) {
return
''
; }
var
a = 0;
var
i = 0;
var
temp =
''
;
for
(i=0;i<str.length;i++)
{
if
(str.charCodeAt(i)>255)
{
a+=2;
}
else
{
a++;
}
if
(a > len) {
return
temp; }
temp += str.charAt(i);
}
return
str;
}
var
str =
"呵呵he哈哈嘿嘿and"
;
document.write(
"字符串:<font color='red'>"
+str+
"</font><br /><br />"
);
document.write(
"javascript 默認截取10個字節的返回值:<br />"
);
document.write(
"<font color='red'>"
+str.substr(0, 10)+
"</font><br /><br
/>"
);
document.write(
"用本文介紹的方法截取10個字節的返回值:<br />"
);
document.write(
"<font color='red'>"
+substr(str, 10)+
"</font><br /><br
/>"
);
document.write(
"截取9個字節的返回值:<br />"
);
document.write(
"<font color='red'>"
+substr(str, 9)+
"</font><br /><br />"
);
</script>