Im writting a function to compare 2 versions, and return true if the second is bigger then first version.
but my algorithm have a "hole", and I cant figure out how fix.
function compareversion(version1,version2){
var result=false;
if(typeof version1!=='object'){ version1=version1.toString().split('.'); }
if(typeof version2!=='object'){ version2=version2.toString().split('.'); }
for(var i=0;i<(Math.max(version1.length,version2.length));i++){
if(version1[i]==undefined){ version1[i]=0; }
if(version2[i]==undefined){ version2[i]=0; }
if(version1[i]<version2[i]){
result=true;
break;
}
}
return(result);
}
this exemples return as expected
compareversion('1','1') //false
compareversion('1','1.0.0') //false
compareversion('2.0','1.0.0') //false
compareversion('1.1','1.2') //true
compareversion('1','1.0.0.1') //true
but this
compareversion('1.1.0','1.0.1') //return true but should be false
This should work:
function compareversion(version1,version2){
var result=false;
if(typeof version1!=='object'){ version1=version1.toString().split('.'); }
if(typeof version2!=='object'){ version2=version2.toString().split('.'); }
for(var i=0;i<(Math.max(version1.length,version2.length));i++){
if(version1[i]==undefined){ version1[i]=0; }
if(version2[i]==undefined){ version2[i]=0; }
if(Number(version1[i])<Number(version2[i])){
result=true;
break;
}
if(version1[i]!=version2[i]){
break;
}
}
return(result);
}
The reason compareversion('1.1.0','1.0.1')
fails is that your code first compares 1
to 1
, then 1
to 0
(it does not break here since it only breaks if version1[i] < version2[i]
) and then 0
to 1
.
Since 0 < 1
, it returns false
.