/// <summary>
/// 數字轉大寫
/// </summary>
/// <param name="Num">數字</param>
/// <returns></returns>

public static string CmycurD(decimal num)
{
string str1 = "零壹貳叁肆伍陸柒捌玖"; //0-9所對應的漢字
string str2 = "萬仟佰拾億仟佰拾萬仟佰拾元角分"; //數字位所對應的漢字
string str3 = ""; //從原num值中取出的值
string str4 = ""; //數字的字符串形式
string str5 = ""; //人民幣大寫金額形式
int i; //循環變量
int j; //num的值乘以100的字符串長度
string ch1 = ""; //數字的漢語讀法
string ch2 = ""; //數字位的漢字讀法
int nzero = 0; //用來計算連續的零值是幾個
int temp; //從原num值中取出的值

num = Math.Round(Math.Abs(num), 2); //將num取絕對值並四舍五入取2位小數
str4 = ((long)(num * 100)).ToString(); //將num乘100並轉換成字符串形式
j = str4.Length; //找出最高位
if (j > 15) { return "溢出"; }
str2 = str2.Substring(15 - j); //取出對應位數的str2的值。如：200.55,j為5所以str2=佰拾元角分

//循環取出每一位需要轉換的值
for (i = 0; i < j; i++)
{
str3 = str4.Substring(i, 1); //取出需轉換的某一位的值
temp = Convert.ToInt32(str3); //轉換為數字
if (i != (j - 3) && i != (j - 7) && i != (j - 11) && i != (j - 15))
{
//當所取位數不為元、萬、億、萬億上的數字時
if (str3 == "0")
{
ch1 = "";
ch2 = "";
nzero = nzero + 1;
}
else
{
if (str3 != "0" && nzero != 0)
{
ch1 = "零" + str1.Substring(temp * 1, 1);
ch2 = str2.Substring(i, 1);
nzero = 0;
}
else
{
ch1 = str1.Substring(temp * 1, 1);
ch2 = str2.Substring(i, 1);
nzero = 0;
}
}
}
else
{
//該位是萬億，億，萬，元位等關鍵位
if (str3 != "0" && nzero != 0)
{
ch1 = "零" + str1.Substring(temp * 1, 1);
ch2 = str2.Substring(i, 1);
nzero = 0;
}
else
{
if (str3 != "0" && nzero == 0)
{
ch1 = str1.Substring(temp * 1, 1);
ch2 = str2.Substring(i, 1);
nzero = 0;
}
else
{
if (str3 == "0" && nzero >= 3)
{
ch1 = "";
ch2 = "";
nzero = nzero + 1;
}
else
{
if (j >= 11)
{
ch1 = "";
nzero = nzero + 1;
}
else
{
ch1 = "";
ch2 = str2.Substring(i, 1);
nzero = nzero + 1;
}
}
}
}
}
if (i == (j - 11) || i == (j - 3))
{
//如果該位是億位或元位，則必須寫上
ch2 = str2.Substring(i, 1);
}
str5 = str5 + ch1 + ch2;

if (i == j - 1 && str3 == "0")
{
//最後一位（分）為0時，加上“整”
str5 = str5 + ‘整‘;
}
}
if (num == 0)
{
str5 = "零元整";
}
return str5;
}

c# 財務報表數字轉大寫的方法