有人请帮助我如何将nsdecimalnumber值转换为String 这是代码。但不工作。
var price = prod.minimumPrice //it return type is NSDecimalnumber Store result is 10
cell.priceLB.text = NSString(format:"%f", prod.minimumPrice) as String// But display result is 0.000
答案 0 :(得分：6)
您可以尝试其中一些选项。它们都应该返回10.还要检查为什么需要创建NSString格式化数字并将其转换为String。
"\(price)"
String(describing: price)
NSString(format: "%@", price)
答案 1 :(得分：3)
NSDecimalValue继承自NSNumber。
NSNumber有stringValue属性
var stringValue: String { get }
The number object's value expressed as a human-readable string.
The string is created by invoking description(withLocale:) where locale is nil.
答案 2 :(得分：1)
两种方式：
使用$ pip install psutil
Collecting psutil
Using cached https://files.pythonhosted.org/packages/1c/ca/5b8c1fe032a458c2c4bcbe509d1401dca9dda35c7fc46b36bb81c2834740/psutil-5.6.3.tar.gz
Building wheels for collected packages: psutil
Building wheel for psutil (setup.py) ... error
ERROR: Command errored out with exit status 1:
command: /opt/anaconda/bin/python -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-ay_2kk3f/psutil/setup.py'"'"'; __file__='"'"'/tmp/pip-install-ay_2kk3f/psutil/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' bdist_wheel -d /tmp/pip-wheel-xsbcm34z --python-tag cp37
cwd: /tmp/pip-install-ay_2kk3f/psutil/
Complete output (61 lines):
running bdist_wheel
running build
running build_py
creating build
creating build/lib.linux-x86_64-3.7
creating build/lib.linux-x86_64-3.7/psutil
copying psutil/_pswindows.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_pssunos.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_psposix.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_psosx.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_pslinux.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_psbsd.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_psaix.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_compat.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_common.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/__init__.py -> build/lib.linux-x86_64-3.7/psutil
creating build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_windows.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_unicode.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_system.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_sunos.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_process.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_posix.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_osx.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_misc.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_memory_leaks.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_linux.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_contracts.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_connections.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_bsd.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_aix.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/runner.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/__main__.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/__init__.py -> build/lib.linux-x86_64-3.7/psutil/tests
running build_ext
building 'psutil._psutil_linux' extension
creating build/temp.linux-x86_64-3.7
creating build/temp.linux-x86_64-3.7/psutil
gcc -pthread -B /opt/anaconda/compiler_compat -Wl,--sysroot=/ -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -DPSUTIL_POSIX=1 -DPSUTIL_VERSION=563 -DPSUTIL_LINUX=1 -I/opt/anaconda/include/python3.7m -c psutil/_psutil_common.c -o build/temp.linux-x86_64-3.7/psutil/_psutil_common.o
gcc -pthread -B /opt/anaconda/compiler_compat -Wl,--sysroot=/ -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -DPSUTIL_POSIX=1 -DPSUTIL_VERSION=563 -DPSUTIL_LINUX=1 -I/opt/anaconda/include/python3.7m -c psutil/_psutil_posix.c -o build/temp.linux-x86_64-3.7/psutil/_psutil_posix.o
psutil/_psutil_posix.c: In function 'psutil_net_if_flags':
psutil/_psutil_posix.c:415:5: warning: 'strncpy' specified bound 16 equals destination size [-Wstringop-truncation]
415 | strncpy(ifr.ifr_name, nic_name, sizeof(ifr.ifr_name));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
psutil/_psutil_posix.c: In function 'psutil_net_if_mtu':
psutil/_psutil_posix.c:376:5: warning: 'strncpy' specified bound 16 equals destination size [-Wstringop-truncation]
376 | strncpy(ifr.ifr_name, nic_name, sizeof(ifr.ifr_name));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
gcc -pthread -B /opt/anaconda/compiler_compat -Wl,--sysroot=/ -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -DPSUTIL_POSIX=1 -DPSUTIL_VERSION=563 -DPSUTIL_LINUX=1 -I/opt/anaconda/include/python3.7m -c psutil/_psutil_linux.c -o build/temp.linux-x86_64-3.7/psutil/_psutil_linux.o
psutil/_psutil_linux.c: In function 'psutil_net_if_duplex_speed':
psutil/_psutil_linux.c:539:5: warning: 'strncpy' specified bound 16 equals destination size [-Wstringop-truncation]
539 | strncpy(ifr.ifr_name, nic_name, sizeof(ifr.ifr_name));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
gcc -pthread -shared -B /opt/anaconda/compiler_compat -L/opt/anaconda/lib -Wl,-rpath=/opt/anaconda/lib -Wl,--no-as-needed -Wl,--sysroot=/ build/temp.linux-x86_64-3.7/psutil/_psutil_common.o build/temp.linux-x86_64-3.7/psutil/_psutil_posix.o build/temp.linux-x86_64-3.7/psutil/_psutil_linux.o -o build/lib.linux-x86_64-3.7/psutil/_psutil_linux.cpython-37m-x86_64-linux-gnu.so
/opt/anaconda/compiler_compat/ld: build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: unable to initialize decompress status for section .debug_info
/opt/anaconda/compiler_compat/ld: build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: unable to initialize decompress status for section .debug_info
/opt/anaconda/compiler_compat/ld: build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: unable to initialize decompress status for section .debug_info
/opt/anaconda/compiler_compat/ld: build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: unable to initialize decompress status for section .debug_info
build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: file not recognized: file format not recognized
collect2: error: ld returned 1 exit status
error: command 'gcc' failed with exit status 1
----------------------------------------
ERROR: Failed building wheel for psutil
Running setup.py clean for psutil
Failed to build psutil
ERROR: spyder 3.3.6 has requirement pyqt5<5.13; python_version >= "3", but you'll have pyqt5 5.13.1 which is incompatible.
ERROR: spyder 3.3.6 has requirement pyqtwebengine<5.13; python_version >= "3", but you'll have pyqtwebengine 5.13.1 which is incompatible.
Installing collected packages: psutil
Running setup.py install for psutil ... error
ERROR: Command errored out with exit status 1:
command: /opt/anaconda/bin/python -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-ay_2kk3f/psutil/setup.py'"'"'; __file__='"'"'/tmp/pip-install-ay_2kk3f/psutil/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-g9lzx155/install-record.txt --single-version-externally-managed --compile
cwd: /tmp/pip-install-ay_2kk3f/psutil/
Complete output (61 lines):
running install
running build
running build_py
creating build
creating build/lib.linux-x86_64-3.7
creating build/lib.linux-x86_64-3.7/psutil
copying psutil/_pswindows.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_pssunos.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_psposix.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_psosx.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_pslinux.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_psbsd.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_psaix.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_compat.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/_common.py -> build/lib.linux-x86_64-3.7/psutil
copying psutil/__init__.py -> build/lib.linux-x86_64-3.7/psutil
creating build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_windows.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_unicode.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_system.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_sunos.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_process.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_posix.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_osx.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_misc.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_memory_leaks.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_linux.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_contracts.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_connections.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_bsd.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/test_aix.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/runner.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/__main__.py -> build/lib.linux-x86_64-3.7/psutil/tests
copying psutil/tests/__init__.py -> build/lib.linux-x86_64-3.7/psutil/tests
running build_ext
building 'psutil._psutil_linux' extension
creating build/temp.linux-x86_64-3.7
creating build/temp.linux-x86_64-3.7/psutil
gcc -pthread -B /opt/anaconda/compiler_compat -Wl,--sysroot=/ -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -DPSUTIL_POSIX=1 -DPSUTIL_VERSION=563 -DPSUTIL_LINUX=1 -I/opt/anaconda/include/python3.7m -c psutil/_psutil_common.c -o build/temp.linux-x86_64-3.7/psutil/_psutil_common.o
gcc -pthread -B /opt/anaconda/compiler_compat -Wl,--sysroot=/ -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -DPSUTIL_POSIX=1 -DPSUTIL_VERSION=563 -DPSUTIL_LINUX=1 -I/opt/anaconda/include/python3.7m -c psutil/_psutil_posix.c -o build/temp.linux-x86_64-3.7/psutil/_psutil_posix.o
psutil/_psutil_posix.c: In function 'psutil_net_if_flags':
psutil/_psutil_posix.c:415:5: warning: 'strncpy' specified bound 16 equals destination size [-Wstringop-truncation]
415 | strncpy(ifr.ifr_name, nic_name, sizeof(ifr.ifr_name));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
psutil/_psutil_posix.c: In function 'psutil_net_if_mtu':
psutil/_psutil_posix.c:376:5: warning: 'strncpy' specified bound 16 equals destination size [-Wstringop-truncation]
376 | strncpy(ifr.ifr_name, nic_name, sizeof(ifr.ifr_name));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
gcc -pthread -B /opt/anaconda/compiler_compat -Wl,--sysroot=/ -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -fPIC -DPSUTIL_POSIX=1 -DPSUTIL_VERSION=563 -DPSUTIL_LINUX=1 -I/opt/anaconda/include/python3.7m -c psutil/_psutil_linux.c -o build/temp.linux-x86_64-3.7/psutil/_psutil_linux.o
psutil/_psutil_linux.c: In function 'psutil_net_if_duplex_speed':
psutil/_psutil_linux.c:539:5: warning: 'strncpy' specified bound 16 equals destination size [-Wstringop-truncation]
539 | strncpy(ifr.ifr_name, nic_name, sizeof(ifr.ifr_name));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
gcc -pthread -shared -B /opt/anaconda/compiler_compat -L/opt/anaconda/lib -Wl,-rpath=/opt/anaconda/lib -Wl,--no-as-needed -Wl,--sysroot=/ build/temp.linux-x86_64-3.7/psutil/_psutil_common.o build/temp.linux-x86_64-3.7/psutil/_psutil_posix.o build/temp.linux-x86_64-3.7/psutil/_psutil_linux.o -o build/lib.linux-x86_64-3.7/psutil/_psutil_linux.cpython-37m-x86_64-linux-gnu.so
/opt/anaconda/compiler_compat/ld: build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: unable to initialize decompress status for section .debug_info
/opt/anaconda/compiler_compat/ld: build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: unable to initialize decompress status for section .debug_info
/opt/anaconda/compiler_compat/ld: build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: unable to initialize decompress status for section .debug_info
/opt/anaconda/compiler_compat/ld: build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: unable to initialize decompress status for section .debug_info
build/temp.linux-x86_64-3.7/psutil/_psutil_common.o: file not recognized: file format not recognized
collect2: error: ld returned 1 exit status
error: command 'gcc' failed with exit status 1
----------------------------------------
ERROR: Command errored out with exit status 1: /opt/anaconda/bin/python -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-ay_2kk3f/psutil/setup.py'"'"'; __file__='"'"'/tmp/pip-install-ay_2kk3f/psutil/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /tmp/pip-record-g9lzx155/install-record.txt --single-version-externally-managed --compile Check the logs for full command output.
直接使用NumberFormatter属性
使用NumberFormatter的代码固定到小数点后两位：
快速5
stringValue答案 3 :(得分：0)
试试这个
var price = prod.minimumPrice
cell.priceLB.text = "\(price)"
//or
cell.priceLB.text = String(describing: price)