Given a string and we have to check whether it contains only digits or not in Python.

给定一个字符串，我们必须检查它在Python中是否仅包含数字。

To check that a string contains only digits (or a string has a number) – we can use isdigit() function, it returns true, if all characters of the string are digits.

要检查字符串是否仅包含数字 (或字符串包含数字 )，可以使用isdigit()函数 ，如果字符串的所有字符均为数字，则返回true 。

Syntax:

句法：

string.isdigit()

Example:

例：

Input:    str1 = "8789"    str2 = "Hello123"    str3 = "123Hello"    str4 = "123 456" #contains space     # function call    str1.isdigit()    str2.isdigit()    str3.isdigit()    str4.isdigit()    Output:    True    False    False    False

Python code to check whether a strings contains a number or not

检查字符串是否包含数字的Python代码

# python program to check whether a string # contains only digits or not # variables declaration & initializationsstr1 = "8789"str2 = "Hello123"str3 = "123Hello"str4 = "123 456"    #contains space # checkingprint("str1.isdigit(): ", str1.isdigit())print("str2.isdigit(): ", str2.isdigit())print("str3.isdigit(): ", str3.isdigit())print("str4.isdigit(): ", str4.isdigit())# checking & printing messagesif str1.isdigit():    print("str1 contains a number")else:    print("str1 does not contain a number")if str2.isdigit():    print("str2 contains a number")else:    print("str2 does not contain a number")if str3.isdigit():    print("str3 contains a number")else:    print("str3 does not contain a number")if str4.isdigit():    print("str4 contains a number")else:    print("str4 does not contain a number")

Output

输出量

str1.isdigit():  Truestr2.isdigit():  Falsestr3.isdigit():  Falsestr4.isdigit():  Falsestr1 contains a numberstr2 does not contain a numberstr3 does not contain a numberstr4 does not contain a number

翻译自: