C#中的常用ToString()方法总结

f
Flags always
d
Integer always
x
Eight digit hex.
Some Useful Examples
String.Format("{0:$#,##0.00;($#,##0.00);Zero}", value); This will output "$1,240.00" if passed 1243.50. It will output the same format but in parentheses if the number is negative, and will output the string "Zero" if the number is zero. String.Format("{0:(###) ###-####}", 18005551212); This will output "(800) 555-1212".
0
{0:00.0000} 1500.4200
placeholder
zeroes.
Digit
#
{0:(#).##} (1500).42
placeholder
Decimal .
point
{0:0.0} 1500.4
Thousand
,
{0:0,0} 1,500
separator
Must be between two zeroes.
c#中的常用 ToString()方法总结
很多类都重写了 ToString 方法， 导致很多类的 tostring 到底执行了什么，有哪些参数， 都不清楚。。。。很郁闷！
对于 int，double 等的 tostring：
C 货币
2.5.ToString("C")
￥2.50
十进制 数D
25.ToString("D5")
00025
E 科学型
25000.ToString("E")
2.500000E+005
F 固定点
25.ToString("F2")
ห้องสมุดไป่ตู้
25.00
G 常规
2.5.ToString("G")
2.5
N 数字
2500000.ToString("N")
2,500,000.00
十六进
制X
255.ToString("X")
offset
{0:zzz} -05:00
:
Separator
{0:hh:mm:ss} 10:43:20
/
Separator
{0:dd/MM/yyyy} 10/12/2002
Enumerations
Specifier
Type
g
Default (Flag names if available, otherwise decimal)
Number ,.
scaling
{0:0,.} 2
Comma adjacent to Period scales by 1000.
% Percent
{0:0%}
150042%
Multiplies by 100, adds % sign.
Exponent
e
{0:00e+0} 15e+2
placeholder
P
数字类型
百分比计数法
432,000.00%
X
只用于整数类
16 进制格式
型
1120 (如果要显示 0x1120，需要写 上 0x)
Custom number formatting:
Specifier Type
Example
Output (Passed Double 1500.42)
Note
Zero
Pads with
{0:MMMM} December
ss Seconds 00-59
{0:ss}
46
tt AM or PM
{0:tt}
PM
yy Year, 2 digits
{0:yy}
02
yyyy Year
{0:yyyy} 2002
Timezone offset, zz
2 digits
{0:zz}
-05
Full timezone zzz
变量.ToString()
字符型转换 转为字符串 12345.ToString("n"); //生成 12,345.00 12345.ToString("C"); //生成 ￥12,345.00 12345.ToString("e"); //生成 1.234500e+004 12345.ToString("f4"); //生成 12345.0000 12345.ToString("x"); //生成 3039 (16 进制) 12345.ToString("p"); //生成 1,234,500.00%
Specifier
Type
Example
Example Output
dd Day
{0:dd}
10
ddd Day name
{0:ddd} Tue
dddd Full day name
{0:dddd} Tuesday
f, ff, ... Second fractions
{0:fff} 932
gg, ... Era
Group
;
see below
separator
Many exponent formats available.
The group separator is especially useful for formatting currency values which require that negative values be enclosed in parentheses. This currency formatting example at the bottom of this document makes it obvious:
U
December 11, 2002 3:13:50 AM
sortable, GMT
Year month
Y
December, 2002
pattern
The 'U' specifier seems broken; that string certainly isn't sortable. Custom date formatting:
FF
格式 符
C
应用 数字类型
含义 专用场合的货币值
示例 $4834.50 (USA)
£4834.50 (UK)
D
只用于整数类型 一般的整数
4834
E
数字类型
科学计数法
4.834E+003
F
数字类型
小数点后的位数固定
4384.50
G
数字类型
一般的数字
4384.5
N
数字类型
通常是专用场合的数字 格式
4,384.50 (UK/USA) 4 384,50 (欧洲大陆)
{0:gg}
A.D.
hh 2 digit hour
{0:hh}
10
2 digit hour, 24hr
HH
{0:HH}
22
format
mm Minute 00-59
{0:mm}
38
MM Month 01-12
{0:MM}
12
Month MMM
abbreviation
{0:MMM} Dec
MMMM Full month name
Full date & time December 10, 2002 10:11:29
F
(long)
PM
Default date &
g
10/12/2002 10:11 PM
time
Default date &
G
10/12/2002 10:11:29 PM
time (long)
Month day M
pattern
Example (Passed System.DateTime.Now)
d
Short date
10/12/2002
D Long date
December 10, 2002
t
Short time
10:11 PM
T
Long time
10:11:29 PM
f
Full date & time December 10, 2002 10:11 PM
Dates
Note that date formatting is especially dependant on the system's regional settings; the example strings here are from my local locale.
Specifier
Type
December 10
RFC1123 date
r
Tue, 10 Dec 2002 22:11:29 GMT
string
Sortable date
s
2002-12-10T22:11:29
string
u
Universal
2002-12-10 22:13:50Z
sortable, local time
Universal