格式化：日期，时间，货币，数字，百分比。
In the report (rdlc) ,
Right Click in the Field, select properties,
Select the Tab Format, and use the format code you need.
d Short date
D Long date
t Short time
T Long time
f Full date/time (short time)
F Full date/time (long time)
g General date/time (short time)
G General date/time (long time)
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