JavaScript determines whether the specified string is a valid number

Source: Internet
Author: User
Keywords Web page production Ajax javascript
Tags ajax function it is javascript return script string text

<cfoutput>
<script type= "Text/javascript Tutorial" >
<!--

function Baseisnotnum (thenum)
{
Judge whether it is a number
if (Basetrim (thenum) = "")
return true;
for (Var i=0;i<thenum.length;i++) {
Onenum=thenum.substring (i,i+1);
if (onenum< "0" | | onenum> "9")
return true;
}
return false;
}

function Baseisnotint (Theint)
{
To determine whether an integer
Theint=basetrim (Theint);
if (theint.length>1 && theint.substring (0,1) = = "0") | | Baseisnotnum (Theint)) {
return true;
}
return false;
}

Function Baseisnotfloat (thefloat)
{
///Determine if floating-point number
Len=thefloat.length;
Dotnum=0;
if (len==0)
return true;
for (Var i=0;i<len;i++) {
onenum=thefloat.substring (i,i+1);
if (onenum==.)
dotnum++;
if ((onenum< "0" | | | onenum> "9") && onenum!= ".") | | DOTNUM>1)
return true;
}
if (len>1 && thefloat.substring (0,1) = = "0") {
if (thefloat.substring (1,2)!= ".")
return true;
}
return false;
}

function Basetrim (str)
{
Remove Space
Lidx=0;ridx=str.length;
if (basetrim.arguments.length==2)
Act=basetrim.arguments[1].tolowercase ();
Else
Act= "All";
for (Var i=0;i<str.length;i++) {
Thelstr=str.substring (lidx,lidx+1);
Therstr=str.substring (ridx,ridx-1);
if ((act== "All" | | act== "left") && thelstr== "") {
lidx++;
}
if ((act== "All" | | act== "right") && therstr== "") {
ridx--;
}
}
Str=str.slice (LIDX,RIDX);
return str;
}

-->
</script>
</cfoutput>

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