javascript实现英文首字母大写

function replaceStr1(str){
str = str.toLowerCase();
var strTemp = ""; //新字符串
for(var i=0;i<str.length;i++){
if(i == 0){
strTemp += str[i].toUpperCase(); //第一个
continue;
}
if(str[i] == " " && i< str.length-1){ //空格后
strTemp += " ";
strTemp += str[i+1].toUpperCase();
i++;
continue;
}
strTemp += str[i];
}
return strTemp;
}

var text = "abcd ABCD efGH";
console.log(replaceStr(text));//Abcd Abcd Efgh
console.log(replaceStr1(text));//Abcd Abcd Efgh