javascript|函数
函数Reset()按Reset按钮后对各字段的内容复位。
函数submitForms()按submit按钮后对字段合法性检查后发送电子邮件。
函数isName()对姓名字段进行合法性检查。
函数isEmail()对电子邮件地址字段进行合法性检查。
函数isBrowser()对浏览器字段与自动检测的浏览器版本进行比较。
函数isCountry()对国家字段进行合法性检查。
函数isComment()对意见字段进行合法性检查，不允许为空值。
函数isFavorite()对喜欢的站点字段进行合法性检查，不允许为空值。
程序中还提供了一些技巧，例如，如何判断浏览器的版本，字符串的操作等等。
结果是以电子邮件的形式提供给你的，里面有客人输入的各个字段。程序比较长，但不难看懂，下面是源代码：
<HTML>
<HEAD>
<TITLE>用JavaScript编制留言簿程序</TITLE>
<SCRIPTLANGUAGE="JavaScript">
<!--Begin
//Someone@abc.com是你自己的电子邮件地址
varemailAddress="Someone@abc.com";
functiontoName()
{
vartoNameval=document.forms[0].elements[1].value;
toNameval="mailto:Someone@abc.com?subject=GuestBookexample";
this.document.mail.action=toNameval;
}
functionReset(){
document.forms[0].elements[0].value="";
document.forms[0].elements[1].value="";
document.forms[0].elements[2].value=
navigator.appName+""+navigator.appVersion;
document.forms[0].elements[3].value="";
document.forms[0].elements[4].value="";
document.forms[0].elements[5].value="";
document.forms[0].elements[0].focus();
}
functionsubmitForms(){
if((isName())&&(isEmail())&&(isBrowser())
&&(isCountry())&&(isComment())&&(isFavorite()))
if(confirm("\nYou'reabouttoe-mailtheform.\n\nClick
onYEStosubmit.\n\nClickonNOtoabort."))
{
alert("\nYoursubmissionwillnowbemadeto:
\n\n"+emailAddress+"\n\n\nThankyou!");
returntrue;
}
else
{
alert("\nYouhavechosentoabortthesubmission.");
returnfalse;
}
else
returnfalse;
}
functionisName(){
varstr=document.forms[0].elements[0].value;
if(str==""){
alert("\nTheNAMEfieldisblank.\n\nPleaseenteryourname.")
document.forms[0].elements[0].focus();
returnfalse;
}
for(vari=0;i<str.length;i++)
{
varch=str.substring(i,i+1);
if(((ch<"a"||"z"<ch)&&(ch<"A"||"Z"<ch))&&ch!='')
{
alert("\nTheNAMEfieldonlyacceptsletters
&spaces.\n\nPleasere-enteryourname.");
document.forms[0].elements[0].select();
document.forms[0].elements[0].focus();
returnfalse;
}
}
returntrue;
}
functionisEmail()
{
emailAddress=document.forms[0].elements[1].value;
if(document.forms[0].elements[1].value==""){
alert("\nTheE-MAILfieldisblank.
\n\nPleaseenteryoure-mailaddress.")
document.forms[0].elements[1].focus();
returnfalse;
}
if(document.forms[0].elements[1].value.indexOf('@',0)==-1||
document.forms[0].elements[1].value.indexOf('.',0)==-1)
{
alert("\nTheE-MAILfieldrequiresa\"@\"
anda\".\"beused.\n\nPleasere-enteryoure-mailaddress.")
document.forms[0].elements[1].select();
document.forms[0].elements[1].focus();
returnfalse;
}
else
{
toName();
returntrue;
}
}
functionisBrowser()
{
if(document.forms[0].elements[2].value!
=navigator.appName+""+navigator.appVersion)
{
if(confirm("\nYou'vechangedyourbrowser
type.\n\nClickonOKtokeepchanges.\
n\nClickonCanceltorestoredetectedbrowser."))
returntrue
else
{
document.forms[0].elements[2].value=
navigator.appName+""+navigator.appVersion;
returntrue;
}
}
else
returntrue;
}
functionisCountry(){
varstr=document.forms[0].elements[3].value;
if(str==""){
alert("\nTheCOUNTRYfieldis
blank.\n\nPleaseenteryourcountry.")
document.forms[0].elements[3].focus();
returnfalse;
}
for(vari=0;i<str.length;i++){
varch=str.substring(i,i+1);
if(((ch<"a"||"z"<ch)&&
(ch<"A"||"Z"<ch))&&ch!='')
{
alert("\nTheCOUNTRYfieldonlyaccepts
letters&spaces.\n\nPleasere-enteryourcountry.");
document.forms[0].elements[3].select();
document.forms[0].elements[3].focus();
returnfalse;
}
}
returntrue;
}
functionisComment(){
if(document.forms[0].elements[4].value==""){
if(confirm("\nYou'reabouttosubmit
withoutleavingacomment.\n\nClick
onCANCELtoincludeacomment.\n\nClick
onOKtocontinuewithoutacomment."))
returntrue
else
{
document.forms[0].elements[4].focus();
returnfalse;
}
}
else
returntrue
}
functionisFavorite(){
if(document.forms[0].elements[5].value==""){
if(confirm("\nYou'reabouttosubmitwithout
listingyourfavoritesites.\n\nClickonCANCEL
toincludefavorites.\n\nClickonOKtocontinue
withoutlistingfavorites."))
returntrue
else
{
document.forms[0].elements[5].focus();
returnfalse;
}
}
else
returntrue
}
//End-->
</SCRIPT>
</HEAD>
<BODY>
<CENTER>
<FORMENCTYPE="text/plain"
NAME="mail"METHOD='GET'
ACTION='mailto:Someone@abc.com'
>
<TABLEBORDER=0WIDTH=400>
<TR>
<TDalign="center"><FONTCOLOR=800000>
<STRONG>Enteryourname:</STRONG></FONT></TD>
<TDalign="center"><FONTCOLOR=800000>
<STRONG>Enteryoure-mailaddress:</STRONG>
</FONT></TD>
</TR>
<TR>
<TDalign="center"><INPUTTYPE="text"
NAME="name"SIZE=30MAXLENGTH=40></TD>
</TD>
<TDalign="center"><INPUTTYPE="text"
NAME="email"SIZE=30MAXLENGTH=40></TD>
</TR>
<TR>
<TDalign="center"><FONTCOLOR=800000>
<STRONG>Yourbrowser</STRONG></FONT></TD>
<TDalign="center"><FONTCOLOR=800000>
<STRONG>Enteryourcountry:</STRONG></FONT></TD>
</TR>
<TR>
<TDalign="center"><INPUTTYPE="text"
NAME="browser"SIZE=30MAXLENGTH=60></TD>
<TDalign="center"><INPUTTYPE="text"
NAME="country"SIZE=30MAXLENGTH=60>
</TD>
</TR>
</TABLE>
<CENTER>
<FONTCOLOR=800000><STRONG>
Leaveacommentorsuggestion:</strong></font><BR>
<TEXTAREANAME="comments"
ROWS=5COLS=50wrap=yes>Comments?
Suggestions?</TEXTAREA><P><P>
<FONTCOLOR=800000><STRONG>
Listyourfavoritesites:</STRONG></FONT><BR>
<TDalign="center"><TEXTAREANAME="favorites"
ROWS=5COLS=50wrap=yes>
AnysitesIshouldtakealookat?</TEXTAREA>
<P><P>
<INPUTTYPE="submit"VALUE="Submit">
<center><INPUTTYPE="reset"VALUE="Reset"
>
</FORM>
</CENTER>
</BODY>
</HTML>