即使期望块返回-1一次迭代，Python中是否有任何方法可以完成for循环的所有迭代？

如何解决即使期望块返回-1一次迭代，Python中是否有任何方法可以完成for循环的所有迭代？

def try():
    for i in range(9):
        try:
           {body}
        except:
            return -1

根据我的理解，如果任何迭代均发生异常，则程序将退出循环并返回-1，而不完成整个循环。我希望程序可以完成循环的其余部分，即使任何迭代都发生异常。

有什么办法吗？

解决方法

您可以像这样：继续而不是返回：

[1,2,3,4,5]
1
[5,5]
2
[5,10,5]
3
[5,15,5]
4
[5,20,5]
5
[5,25]

,

xlist=[1,'THREE',5]
print(xlist)

for item in xlist:

    try:
        xlist[xlist.index(item)] = item / 5
    except:
        xlist[xlist.index(item)] = item
    finally:
        print(item)

print(xlist)

,

您可以为此目的使用def printList1(list,col,STR_FMT='{}',gap=1): list = [STR_FMT.format(x).lstrip() for x in list] FMT2 = '%%%ds%%s' % (max(len(x) for x in list)+gap) print(''.join([FMT2 % (v,"" if (i+1) % col else "\n") for i,v in enumerate(list)])) 和def printList2(list,col=None,gap=2,uniform=True,ljust=True,STR_FMT="{}",MAX_CHARS=120,end='\n'): list = [STR_FMT.format(x).strip() for x in list] Lmax,valid,valid_prev,cp,c = [MAX_CHARS+1],None,1,max(col,1) if col else 1 LoL_prev,Lmax_prev = [],[] while True: LoL = [list[i::c] for i in range(c)] Lmax = [max(len(x)+gap for x in L) for L in LoL] # Find max width of each column with gap width if uniform: # Set each max column width to max across entire set. Lmax = [max(Lmax) for m in Lmax] valid_prev,valid = valid,sum(Lmax) <= MAX_CHARS if (col and (valid or (c == 1))) or not MAX_CHARS: # If column and valid strlen or MAX_CHARS is empty break elif valid_prev and not valid_prev == valid: # If valid_prev exist c = cp if valid_prev and not valid else c LoL,Lmax = (LoL_prev,Lmax_prev) if valid_prev else (LoL,Lmax) break LoL_prev,Lmax_prev = LoL,Lmax cp,c = c,(c + (+1 if valid else -1)) ljust = '-' if ljust else '' FMT = ["%%%s%ds%s" % (ljust,max(Lmax) if uniform else m,end if i+1 == c else '') for i,m in enumerate(Lmax)] outStr = ''.join([''.join([f % v for v,f in zip(L,FMT)]) for L in zip(*LoL)]) remStr = ''.join([f % v for v,f in zip(list[c * (len(list) // c):],FMT)]) print(outStr+(remStr+end if remStr else remStr),end='')

如果您希望在>>> foolist = ['exiv2-devel','mingw-libs','tcltk-demos','fcgi','netcdf','pdcurses-devel','msvcrt','gdal-grass','iconv','qgis-devel','qgis1.1','php_mapscript'] >>> printList2(foolist) exiv2-devel mingw-libs tcltk-demos fcgi netcdf pdcurses-devel msvcrt gdal-grass iconv qgis-devel qgis1.1 php_mapscript >>> printList2(foolist,MAX_CHARS=48,uniform=False,gap=3) exiv2-devel mingw-libs tcltk-demos fcgi netcdf pdcurses-devel msvcrt gdal-grass iconv qgis-devel qgis1.1 php_mapscript >>> printList2(foolist,col=2,gap=3) exiv2-devel mingw-libs tcltk-demos fcgi netcdf pdcurses-devel msvcrt gdal-grass iconv qgis-devel qgis1.1 php_mapscript >>> printList2(foolist,ljust=False,gap=2) exiv2-devel mingw-libs tcltk-demos fcgi netcdf pdcurses-devel msvcrt gdal-grass iconv qgis-devel qgis1.1 php_mapscript >>> printList2(foolist,col=10,gap=2) exiv2-devel mingw-libs tcltk-demos fcgi netcdf pdcurses-devel msvcrt gdal-grass iconv qgis-devel qgis1.1 php_mapscript >>> from math import pi >>> FloatList = [pi**(i+1) for i in range(32)] >>> printList2(FloatList,STR_FMT="{:.5g},",col=7,ljust=False) 3.1416,9.8696,31.006,97.409,306.02,961.39,3020.3,9488.5,29809,93648,2.942e+05,9.2427e+05,2.9037e+06,9.1222e+06,2.8658e+07,9.0032e+07,2.8284e+08,8.8858e+08,2.7916e+09,8.77e+09,2.7552e+10,8.6556e+10,2.7192e+11,8.5427e+11,2.6838e+12,8.4313e+12,2.6488e+13,8.3214e+13,2.6142e+14,8.2129e+14,2.5802e+15,8.1058e+15,块之后执行语句，请使用pass

如果要继续下一次迭代，请使用continue

例如：

try-except

如果您想pass，则应使用continue。

def try():
    for i in range(9):
        try:
           {body}
        except:
            pass
        print('execute')

由于print('execute')之后没有要执行的语句，因此可以使用pass，但是使用def try(): for i in range(9): try: {body} except: continue 不会改变逻辑。