问题

我需要将输入限制为最多5位数字。

```python
def validate(S):
    try:
        float(S)
        return True
    except ValueError:
        messagebox.showerror(message="数据错误，仅限数字。", title="错误")
        return False

e1 = tk.Entry(master, validate="key", validatecommand=(master.register(validate), '%S'))

我有这个方法来接收和验证输入，但我想知道如何在输入上设置最多5位数字的限制。

我尝试过使用此问题中使用的方法（https://stackoverflow.com/questions/5446553/tkinter-entry-character-limit），但在validate方法中不起作用。

<details>
<summary>英文:</summary>

I need to limit the entry to a maximum of 5 digits.

def validate(S):
try:
float(S)
return True
except ValueError:
messagebox.showerror(message="Datos erroneos, únicamente números.", title="ERROR")
return False

e1 = tk.Entry(master, validate="key", validatecommand=(master.register(validate), '%S'))

I have this method to receive and validate that it's just numbers at the entry, but i would like to know how can I put a max limit of 5 digits on the entry.

I tried with the methods used in this question (https://stackoverflow.com/questions/5446553/tkinter-entry-character-limit) but it is not working with the validate method.



</details>


# 答案1
**得分**: 3

从validate函数中返回False，如果字符串的长度超过5。

```python
def validate(S):
    try:
        float(S)
        return len(S) <= 5
    except ValueError:
        messagebox.showerror(message="Datos erroneos, únicamente números.", title="ERROR")
        return False

def validate(S):
    try:
        float(S)
        return len(S) <= 5
    except ValueError:
        messagebox.showerror(message="Datos erroneos, únicamente números.", title="ERROR")
        return False