C#String.PadLeft函數，文本對齊以及填補解決方案

由於很多時候我們需要把數據進行格式化，方便各個系統之間通信和數據交互，因此難免會經常讓人位數不夠而進行位數相應數據填充。比如，你希望獲取的是7位的2進制數據格式，而2進制數據格式，都是以0，1都為數據信號的，只有1,0兩數據格式，剛我說的是7位，相當於如下：1000101格式，如果，我的數據是101三個長度的2進制數據，但我想返回一個新的並且具有固定長度，位數不夠填充0的做法。

string SourceStr="101";

string DestinationStr;

DestinationStr=String.PadLeft(7,"0");

Console.Write(DestinationStr);

以上代碼就會輸出：0000101

現在解析此函數，此函數有2個重載版本。

重載1：public string PadLeft(int totalWidth);

重載2public string PadLeft(int totalWidth, char paddingChar);

關於重載1的解釋，微軟的注釋為：(這個默認是以空格進行左邊填充，保持右邊對齊。)

//
    // Summary:
    //     Right-aligns the characters in this instance, padding with spaces on the
    //     left for a specified total length.
    //
    // Parameters:
    //   totalWidth:
    //     The number of characters in the resulting string, equal to the number of
    //     original characters plus any additional padding characters.
    //
    // Returns:
    //     A new System.String that is equivalent to this instance, but right-aligned
    //     and padded on the left with as many spaces as needed to create a length of
    //     totalWidth. Or, if totalWidth is less than the length of this instance, a
    //     new System.String object that is identical to this instance.
    //
    // Exceptions:
    //   System.ArgumentOutOfRangeException:
    //     totalWidth is less than zero.
    public string PadLeft(int totalWidth);

而重載2的注釋為：（可以根據自己想要填充的字符進行填充，對齊是字符串右對齊。）

 

代碼

//
    // Summary:
    //     Right-aligns the characters in this instance, padding on the left with a
    //     specified Unicode character for a specified total length.
    //
    // Parameters:
    //   totalWidth:
    //     The number of characters in the resulting string, equal to the number of
    //     original characters plus any additional padding characters.
    //
    //   paddingChar:
    //     A Unicode padding character.
    //
    // Returns:
    //     A new System.String that is equivalent to this instance, but right-aligned
    //     and padded on the left with as many paddingChar characters as needed to create
    //     a length of totalWidth. Or, if totalWidth is less than the length of this
    //     instance, a new System.String that is identical to this instance.
    //