JavaScript中的字符串格式，帶逗號

Question

讓我們讓用戶地址的某些部分應以單個字符串格式設置。
地址組件是

Street  
City  
Phone  
State  
Zip  

並應格式化為string street city, phone, state zip 。 （2個逗號）。
問題是每個字段都可以為null 。 因此，如果street == null和city == null ，那么我應該有phone, state zip字串phone, state zip （1個逗號）。 問題在於控制空格數和逗號數
如何避免和減少空檢查的數量？
我當前的代碼是

  var formatAddress = function(address) {
     var retVal = ""

     if (address.street || address.city)
     {
        retVal += address.street ? address.street + " " : "" 
        retVal += address.city ? address.city : "" 
        retVal += ", ";
     }
     retVal += address.phone ? address.phone + ", " : ""

     retVal += address.state ? address.state : ""
     retVal += address.zip ? " " + address.zip : ""  

     return retVal
  }

Answer 1

var fields = [[address.street, address.city], [address.phone], [address.state, address.zip]];
return fields.map(function(part) {
    return part.filter(Boolean).join(" ");
}).filter(function(str) { return str.length; }).join(", ");

或者，在循環中並且沒有filter和map ，而是將屬性名稱映射到它們的值：

var fields = [["street", "city"], ["phone"], ["state", "zip"]];
for (var strs=[], i=0; i<fields.length; i++) {
    for (var parts=[], j=0; j<fields[i].length; j++)
        if (address[fields[i][j]])
            parts.push(address[fields[i][j]]);
    if (parts.length)
        strs.push(parts.join(" "));
}
return strs.join(", ");

Answer 2

將其添加到數組中，並刪除一些相鄰的逗號和空格。

var street = "street";
var city = "city";
var phone = "phone";
var state = "state";
var zip = "zip";
[
    street,
    city, ",",
    phone, ",",
    state,
    zip
].join(" ") //add all items with spaces in between
.replace(/(\s*,\s*)+/g, ", ") //remove multiple spaces before or after commas
.replace(/\s+/g, " "); //remove any other double spaces

Answer 3

可以使用以下功能更清潔：

function formatAddressPart(part,concatString){
     return part ? part+concatString : "";
}


var formatAddress = function(address) {
     var retVal = ""

     if (address.street || address.city)
     {
        retVal += formatAddressPart(address.street, " ");
        retVal += formatAddressPart(address.city,""); 
        retVal += ", ";
     }
     retVal += formatAddressPart(address.phone,", ");

     retVal += formatAddressPart(address.state," ");
     retVal += formatAddressPart(address.zip,"");  

     return retVal
  }

Answer 4

將您的字符串放入數組中，然后使用join方法並用一個來刪除多像素連續逗號

a = [address.Street, 
     address.City, 
     address.Phone, 
     address.State, 
     address.Zip].join (', ').replace (/(, ){2,}/g, ', ');